An agreement question with a verb and a pronoun tests two separate number matches. Start by sorting each part by number. A regular present-tense verb takes -s for one thing and no -s for more than one. Then find the true subject by asking who or what is doing something, reading past phrases and extra information. The pronoun matches its own noun in number, so ask what it stands for rather than copying the subject’s number.
Hints
- Hint 1
In the sentence with the blank, set aside the words between the paired dashes. What is doing the grouping?
- Hint 2
What do scholars examine without handling the originals? Use that phrase to find what the pronoun stands for.
- Hint 3
Once you’ve found what does the grouping and what gets grouped, check each noun’s number separately. Does each name one thing or more than one?
Step-by-step
Check two number matches
Step 1Sort the two parts
The choices pair a verb with a pronoun, so completing _____ by plant family calls for two separate number checks. Sort the verbs first: groups goes with one thing, while group goes with more than one. The pronouns have their own split: it stands for one thing, and them stands for more than one.
- Step 2
Find what does the grouping
What does the grouping? Set aside created after curators at several museums scanned fragile field notebooks, the extra information between the dashes, because it tells us how the catalog was made. Then set aside of botanical illustrations, which tells us what the catalog contains, leaving A digital catalog next to the blank. The true subject is one catalog, not the plural nouns inside those phrases. It’s one catalog even though it holds many illustrations, so its verb must be singular.
- Step 3
Find what gets grouped
The pronoun needs a separate noun: what gets grouped? The opening phrase names botanical illustrations, and enabling scholars to examine related illustrations without handling the originals shows why they’re grouped by family. Scholars use the catalog to examine illustrations that are related to one another, so the pronoun stands for the plural illustrations.
- Step 4
Test the short sentence
Which pairing works in the short version? It groups them by plant family passes both checks, because one catalog groups several illustrations. The choice groups them supplies the singular verb and plural pronoun that short sentence needs. Choice A.