Punctuating “however”, “though” and other transitions

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Difficulty: Advanced
Estimated time: 30 minutes
Practice: Boundaries question bank

What you’ll learn

Recognize a transition question: the same word in every choice, with the marks moving around it.
Cover the transition, split the sentence, and spot the comma splice that commas around it can hide.
Start the second sentence with a transition, or end the first with it, whichever its meaning calls for.
Tell “though” the transition from a “though” that means “although.”
Set off a transition inside one sentence with a pair of commas.
Rule out choices by grammar first, then pick the side, one routine for every transition question.

Prerequisites

Why this matters on the SAT

Which side of the transition?

A transition like “however” or “though” links two ideas, but it can't hold two sentences together. On the SAT, every choice holds the same transition, and only the marks around it move: a comma, a semicolon or a period, before it or after it. So the question looks like one about commas, but it's really asking one thing: does the first sentence end before the transition or after it? Sometimes the answer is neither, because there's only one sentence. These questions don't come up often, but most of them are hard, because the right side is often not the one you'd expect.

Solution to the example

Cover “however” and split. The two sides, many astronomers assumed that the faint smudge … was part of our own galaxy and later observations showed that it lay far beyond the Milky Way, can each stand alone, so a period or a semicolon has to go on one side of “however”. The second sentence goes against the first, so “however” starts it: a semicolon before it, a comma after it. The answer is D. A tempts most, because commas so often surround “however”, but cover it and only commas stand between two full sentences, a comma splice. B has no mark before “however”, so nothing ends the first sentence. C ends the first sentence with “however”, which would turn it against a sentence before it, and there isn't one.

SAT example

In the early 1900s, many astronomers assumed that the faint smudge in the Andromeda constellation was part of our own ______ later observations showed that it lay far beyond the Milky Way.

Which choice completes the text so that it conforms to the conventions of Standard English?

A
galaxy, however,
B
galaxy however,
C
galaxy, however;
D
galaxy; however,

A transition can't join two sentences

A transition is a word or phrase like “however”, “therefore” or “for example” that says how one idea relates to another. It links the meaning, but it doesn't join the grammar. Between two full sentences, a transition with commas around it still leaves a comma splice. The sentences need a period or a semicolon (or a colon, when the second explains the first).

In the examples, the spot the choices test is bold, and words a test removes are struck through.

Correct: The night train is slow, but it costs half as much as a flight.
Wrong: Comma splice: The night train is slow, however, it costs half as much as a flight.
Note: Cover the transition: The night train is slow, ~~however,~~ it costs half as much as a flight.

“But” and “however” mean nearly the same thing here, but only “but” is a joining word, so only “but” can join two sentences with a comma. Cover “however”, and a comma by itself is left between two full sentences. The commas around a transition hide the splice.

Lesson 2 called words like “however” look-alikes. Every transition works the same way, whatever its job:

What the transition does	Transitions
goes against the sentence before	“however”, “though”, “even so”, “nevertheless”
gives a result	“therefore”, “as a result”, “consequently”
gives an example	“for example”, “for instance”
says what's true instead	“rather”, “instead”
adds or stresses a point	“in fact”, “moreover”, “indeed”
says when	“later”, “meanwhile”, “today”

Choosing which transition fits a passage is a different question, taught in the Expression of Ideas course's lessons on transitions. In this lesson, the passage has already chosen the word, and your job is to punctuate it.

Starting a sentence: a period or semicolon before, a comma after

When a transition starts the second of two sentences, a period or a semicolon goes before it and a comma after it. The transition then says how the second sentence relates to the first.

Correct: The night train is slow; however, it costs half as much as a flight.
Correct: The night train is slow. However, it costs half as much as a flight.
Correct: The night train is cheap; therefore, it sells out weeks ahead.
Correct: The night train is cheap; for example, a seat to the coast costs less than a taxi to the airport.

“However” turns the second sentence against the first: the train is slow, but it's cheap. “Therefore” makes the second sentence a result of the first, and “for example” makes it an example. The period and the semicolon do the same job, as they do between any two full sentences, so if both appear in the same spot in the choices, they cancel out.

The comma after the transition sets it off from the rest of its sentence, the way one comma closes extra information that opens a sentence in lesson 3. This is the version most students know, and it's right whenever the transition fits the second sentence. But on the SAT, “however” and “though” more often end the first sentence.

Check your understanding:

Correct or comma splice? The bridge reopened in May, therefore, the ferry stopped running.

In this question, cover “however” and split, then check whether it fits at the start of the second sentence.

A growing transit system

Practice problem

The city’s transit system has expanded rapidly over the past ____ ridership has not increased at the same rate.

Which choice completes the text so that it conforms to the conventions of Standard English?

If it doesn't fit the second sentence, it ends the first

A transition can also end the first sentence, with a comma before it and a period or a semicolon after it. Wherever it sits, a transition links its own sentence to the one before it. So at the end of the first sentence, it links the first sentence to the sentence before that one.

Correct: Most night trains in the region were cut years ago. This one still runs, however; it carries the mail to the mountain villages.
Wrong: Wrong side: Most night trains in the region were cut years ago. This one still runs; however, it carries the mail to the mountain villages.

In the first version, “however” sets This one still runs against Most night trains in the region were cut years ago. The sentence after the semicolon says why this train still runs, and a reason can't start with a word that turns against what it explains:

Note: Read it first: However, it carries the mail to the mountain villages.

That gives the test for the side. Read the second sentence with the transition at its start. If the transition fits there, it starts that sentence. If not, it ends the first, and then the first sentence has to relate that way to the sentence before. (“Though” is the exception: as a transition, it never starts a sentence, as the next section shows.)

Note: Read it first: However, it costs half as much as a flight.
Wrong: Wrong side: The night train is slow, however; it costs half as much as a flight.

However, it costs half as much as a flight fits, since a low fare goes against a slow trip, so “however” starts that sentence, as in the last section. At the end of The night train is slow, it would turn that sentence against one before it, and there isn't one.

The SAT tests this side most, and it catches students who know only the other one. The usual shape: the first sentence turns against the one before it, often by saying what's not true, and the second explains or backs it up. But a not alone doesn't decide the side. After The night train doesn't stop at the airport, a sentence that says what it does instead fits “instead” at its start: The night train doesn't stop at the airport; instead, it stops in the old town. The test is always the meaning of the second sentence.

When what follows explains the first sentence, a colon can take the semicolon's place after the transition: This one still runs, however: it carries the mail to the mountain villages. Before a list, the colon is the mark after the transition: Most night trains in the region were cut years ago. Three still run, however: the Lark, the Comet, and the Owl. A colon can't go before a transition that turns the second sentence against the first, because what follows a colon explains what comes before it. Lesson 6 covers colons.

Check your understanding:

Which goes at the blank: smooth; however, it or smooth, however; it? Most of the island’s roads are unpaved. The coast road is ______ was rebuilt last summer.

In this question, read the second sentence with “however” at its start, and if it doesn't fit there, let “however” end the first sentence.

Cobalt-blue glaze

Practice problem

For decades, archaeologists assumed that the cobalt-blue glaze on bowls excavated at an inland settlement had been imported from workshops near the coast. Spectroscopic analysis points to a _____ the glaze's unusual ratio of cobalt to nickel closely matches that of ore from hills just north of the settlement.

Which choice completes the text so that it conforms to the conventions of Standard English?

“Though” at the start means “although”

After “however”, “though” is the SAT's most common transition, and it has a trap of its own. As a transition, “though” ends its sentence or sits inside it, set off by commas. At the start of a clause, it means “although”, so the clause leans on another sentence.

Correct: The night train is slow. It's cheap, though; a seat costs half as much as a flight.
Wrong: Fragment: The night train is slow. It's cheap; though a seat costs half as much as a flight.
Wrong: Starts with “though”: The night train is slow. It's cheap. Though, a seat costs half as much as a flight.

With no comma after it, though a seat costs half as much as a flight means although a seat costs half as much as a flight. That part leans, so a semicolon or a period in front of it leaves a fragment. And “though” the transition never opens a sentence, so Though, with a comma after it is wrong too.

The hardest version has a comma before “though” and no mark after it. Then “though” starts the second part as “although”, and the grammar works. Only the meaning can rule it out:

Wrong: Wrong meaning: The night train is slow. It's cheap, though a seat costs half as much as a flight.
Correct: The night train is slow, though a seat costs half as much as a flight.

To tell them apart, swap in “although”. It's cheap, although a seat costs half as much as a flight makes no sense: the low fare shows the train is cheap; it isn't a point against it. The night train is slow, although a seat costs half as much as a flight works: the low fare goes against the slow trip. If “although” makes sense, “though” can start the part with no mark after it. If not, “though” is the transition, and it ends the first sentence.

“Though” can also start a whole sentence as “although”: Though the night train is slow, it costs half as much as a flight. The rules in this section are about “though” the transition.

Check your understanding:

Which goes at the blank: errors, though or errors, though;? The old map looks accurate. It is full of ______ several of its rivers flow the wrong way.

In this question, rule out “though” after a semicolon, then swap in “although” to test the choice with no mark after “though”.

A confidential interview

Practice problem

To encourage candid feedback about a new city transit app, researchers told participants that the interview would remain confidential. It was not entirely ______ the moderator occasionally repeated a participant’s comment to the group and asked others to weigh in.

Which choice completes the text so that it conforms to the conventions of Standard English?

In one sentence, a pair of commas

Sometimes the split finds only one full sentence. When one side can't stand alone, no period or semicolon goes beside the transition. It sits inside one sentence, set off by a pair of commas, the way extra information is in lesson 3. (Before a list, a colon follows the transition instead, as the section on ending the first sentence showed.)

Back to the night train that still runs after most were cut. The next words can be an -ing phrase instead of a second sentence:

Correct: This one still runs, however, carrying the mail to the mountain villages.
Wrong: Fragment: This one still runs; however, carrying the mail to the mountain villages.
Wrong: Fragment: This one still runs, however; carrying the mail to the mountain villages.
Wrong: Missing comma: This one still runs, however carrying the mail to the mountain villages.

Carrying the mail to the mountain villages has no subject, and carrying is an -ing word with no helper, so it can't stand alone. A semicolon on either side of “however” leaves a fragment. With a comma on each side, “however” sits inside the one sentence; the last version opens the pair and never closes it. Watch for an -ing phrase with no main verb, a because part or an opening phrase at the blank: none of them can stand alone, so the transition stays inside one sentence. An -ing phrase followed by a main verb is different: as lesson 2 showed, it can be the subject of a full sentence, so read on before you decide.

Correct: This one still runs, however, because it carries the mail to the mountain villages.
Correct: To save money, though, many riders take the night train.

A transition can sit in the middle of a sentence, too. Cross out the pair, and the sentence still works:

Correct: The night train, however, still runs every evening.
Note: Cross it out: The night train~~, however,~~ still runs every evening.

When a transition sits inside the second of two sentences, the period or semicolon still goes between the sentences: Most night trains were cut years ago; this one, however, still runs. On the SAT, only commas set off a transition, never dashes or parentheses.

In this question, check whether the words after the blank can stand alone before you put a semicolon beside “however”.

A film’s original ending

Practice problem

Early screenings of a film adaptation ended with a triumphant montage, a change that pleased the studio executives. The director ultimately restored the novel’s original _____ arguing that the story’s quiet grief would otherwise be erased.

Which choice completes the text so that it conforms to the conventions of Standard English?

Grammar first, then the side

Here's the move that makes these questions faster. Most wrong choices break a rule you can check without reading for meaning: only commas between two full sentences, no period or semicolon at all, a period and a semicolon in the same spot, a missing comma beside the transition, or a “though” right after a period or a semicolon, with only one clause after it. Cross those out first. Often one choice is left. When two are left, the meaning decides, usually which side the transition goes on.

That makes one routine for every transition question, the one the worked examples and the practice problems follow:

Cover and split. Cover the transition and ask of each side: could it stand alone? If one side can't, the transition takes a pair of commas, unless a list follows it (then a colon).
Cross out what breaks the grammar: a comma splice, a run-on, marks that do the same job, a missing comma beside the transition, and a “though” right after a period or a semicolon, with only one clause after it.
Pick the side. Read the second sentence with the transition at its start. If it fits, it starts that sentence; if not, it ends the first. For “though” with no mark after it, swap in “although”.

Example: “however” at the end of a sentence

In this question, two choices put “however” at the start of the second sentence, and the first sentence says what the lines are not.

Worked example

The faint lines crossing the glaze of a twelfth-century ceramic bowl appear irregular, so conservators initially thought they were cracks formed during firing. The lines are not _____ under magnification, each follows the same repeated wave pattern, suggesting that the potter deliberately incised them.

Which choice completes the text so that it conforms to the conventions of Standard English?

A
random. However,
B
random; however,
C
random, however;
D
random, however,

Step 1

Cover “however” and split

The choices differ only in the marks around “however” after random, so this is a transition question. Cover “however” and split. The lines are not random has lines and are as its subject and main verb, and under magnification, each follows the same repeated wave pattern has each and follows. Both sides can stand alone, so a period or a semicolon has to go on one side of “however”.

Step 2

Cross out the marks that do the same job

A puts a period before “However”, and B puts a semicolon before “however”. Both start the second sentence with it, so they do the same job and cancel out. D puts a comma on each side of “however”. Cover it, and only commas stand between two full sentences, a comma splice. That leaves C.

Step 3

Check the side by meaning

B tempts most, because a semicolon before “however” is the version everyone knows. The meaning rules it out too. Read the second sentence with “however” at its start: However, under magnification, each follows the same repeated wave pattern … That doesn't turn against The lines are not random; it's the evidence for it.

So “however” ends the first sentence and sets The lines are not random against the sentence before, where the lines appear irregular, so conservators initially thought they were cracks. The answer is C.

Correct: The lines are not random, however; under magnification, each follows the same repeated wave pattern.

Example: “though” or “although”?

In this question, the transition is “though”, and one choice reads smoothly with “though” as “although”.

Worked example

To help museum curators keep up with incoming donations, a team of developers built an app that lets volunteers photograph objects and upload descriptions. The app was intended to speed cataloging. It can occasionally slow the review _____ sorting hundreds of nearly identical submissions requires extra staff time.

Which choice completes the text so that it conforms to the conventions of Standard English?

A
process, though;
B
process, though
C
process; though
D
process, though,

Step 1

Cover “though” and split

The choices move the marks around “though” after process. Cover it and split. It can occasionally slow the review process can stand alone. After the blank, read on for the main verb, requires. What requires extra staff time? Sorting hundreds of nearly identical submissions: the whole -ing phrase is the subject, so that side can stand alone too. Two full sentences need a period or a semicolon, so D's pair of commas makes a comma splice.

Step 2

Rule out “though” after a semicolon

C puts a semicolon before “though”, with no comma after it. At the start of a clause, “though” means “although”, so though sorting hundreds of nearly identical submissions requires extra staff time leans on another sentence. After a semicolon, it's a fragment.

Step 3

Swap in “although” to test B

B tempts most, because it reads smoothly. With no mark after “though”, B makes it start the second part, so swap in “although”: It can occasionally slow the review process, although sorting hundreds of nearly identical submissions requires extra staff time. That treats the extra staff time as a point against the slower review, but it's the reason the review slows. So B says the wrong thing.

Step 4

“Though” ends the first sentence

In A, “though” ends the first sentence and sets It can occasionally slow the review process against The app was intended to speed cataloging. The semicolon then joins the reason it slows. The answer is A.

Correct: It can occasionally slow the review process, though; sorting hundreds of nearly identical submissions requires extra staff time.

Practice problems

These questions mix the cases, so run the whole routine on each one: cover and split, cross out what breaks the grammar, then pick the side.

Flashing plankton

Practice problem

Some bioluminescent dinoflagellates do not glow _____ they emit brief flashes when the surrounding water is disturbed.

Which choice completes the text so that it conforms to the conventions of Standard English?

A painting after a flood

Practice problem

Early entries in a museum catalog suggested that a painting could not be fully restored after _____ conservators later revived many of its original colors.

Which choice completes the text so that it conforms to the conventions of Standard English?

Shipping logs and letters

Practice problem

Historian Rahul Singh is known for assembling large databases of shipping logs from the eighteenth century. A hallmark of his ______ is his habit of reading sailors’ personal letters alongside the numerical records.

Which choice completes the text so that it conforms to the conventions of Standard English?

A park that shows its drainage

Practice problem

In designing a new city park, landscape architect Mei Chen studied how stormwater moves through a neighborhood. Chen didn’t treat drainage as a purely technical ______ she used swales and native plants to make the system visible to visitors.

Which choice completes the text so that it conforms to the conventions of Standard English?

An avalanche model

Practice problem

To decide when to close the mountain pass, the transportation agency consulted a new avalanche-forecasting model. The agency couldn’t base its decision on the model ______ because the model’s creators had trained it on data from just two winters, both atypically dry.

Which choice completes the text so that it conforms to the conventions of Standard English?

Finish the lesson

9 practice examples left

Finish the remaining questions correctly to complete this lesson.

Quick recap

A transition can't join two sentences. Cover it and split: commas around it between two full sentences still leave a comma splice.
It starts the second sentence if it fits there (slow; however, it), and ends the first if not (runs, however; it).
As a transition, “though” never starts a sentence. At the start of a clause, it means “although”.
Inside one sentence, a pair of commas sets the transition off, unless a list follows it (then a colon).
Every question: cover and split, cross out what breaks the grammar, then pick the side.

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