A verb form question tests whether a word completes a sentence or describes a noun. Find the noun the sentence is about and read to the period for its main verb, which says what that noun does or is. Adding another main verb needs a joining word or suitable punctuation. If the blank describes a noun, ask who acts: -ing describes the noun doing something, while -ed can describe something done to it.
Hints
- Hint 1
Read the whole sentence, including the words after the second comma. Find the verb that says what the wing does.
- Hint 2
Check who does the work in the detail between the commas. Does the wing do something, or does someone do something to the wing?
Step-by-step
Count the main verbs, then test the description
Step 1Find the wing's main verb
Sort the forms first: designs and design can be main verbs, while designing needs a helper such as is to be one. The -ed form can be a main verb or describe a noun. Read on: what "features interactive exhibits"? The "science museum's new wing" is the subject, what the sentence is about, and its main verb is already there: features.
- Step 2
Decide what the blank adds
What can the words between the commas add? ______ to celebrate the centennial of space exploration gives a detail about the wing. No joining word connects another main verb to features, so the blank needs a describing form. Designs and design would add another main verb without a joining word.
- Step 3
Use the was test
Try the was test: put was before an -ed form and ask whether something was done to the noun. The wing was designed to celebrate the centennial of space exploration makes sense because someone planned the wing. Designed fits that meaning; designing would make the wing the one doing the planning. Choice C.