Question

We must finish it ____ we leave.​

Answer 1

Explanation:

when ...... is the answer

Answer 2

We must finish it before we leave.

Explanation:

• The word "before" is used here because of the word "must". "Must" gives the strong condition for one to complete the task.
• We use "must" to show the necessity of the task to be completed.
• So, accordingly, in this sentence, the speaker along with their associates must finish the task "before" they leave.
• The word "before" fits perfectly with the sentence.