Prepositions and Conjunctions — Answer Key
Part A: Fix the Sentence
Each sentence has an error. Rewrite it correctly on the line.
1. Fix the sentence:
We brushed our teeth since dinner.
Corrected: We brushed our teeth after dinner.
After shows one event follows another; since marks a starting moment continuing to now.
2. Fix the sentence:
I have lived here during three years.
Corrected: I have lived here for three years.
Use during with named events; for measures duration like three years across time.
3. Fix the sentence:
Wait at the door until I will return.
Corrected: Wait at the door until I return.
Time clauses with until take present tense to show the future moment ahead.
Part B: Fill in the Blank
Write the missing word or number on each line.
1. Wash your hands before you eat lunch.
Before places one action earlier than another in a clear time order.
2. We stayed quiet during the entire movie.
During shows action happening across the whole length of a named event.
3. Mia has played piano since she was six.
Since marks a beginning point that continues up to the present moment.
4. Please read quietly until the bell rings.
Until marks the time when an ongoing action will finally stop.
Part C: Short Answer
Answer each question in one or two complete sentences.
1. Write one sentence using the preposition before about your morning.
Sample answer: I always pack my backpack before I leave for school.
Before connects two actions and shows which one happens first in time.
2. Explain how since and until are different.
Sample answer: Since marks when something started; until marks when it will stop.
Since shows a beginning continuing to now; until shows the stopping moment.