Choose the correct form of the verb given in the bracket that completes the sentence correctly:We _____ our lunch half an hour ago. (Finish)

The correct answer is C. finished.

The sentence is in the simple past tense, which indicates that the action of finishing lunch happened at a specific point in time in the past. The other options are not in the simple past tense.

• Had finished is in the past perfect tense, which indicates that the action of finishing lunch happened before another action in the past.
• Would have finished is in the conditional perfect tense, which indicates that the action of finishing lunch would have happened if a condition had been met.
• Have finished is in the present perfect tense, which indicates that the action of finishing lunch has happened at some point in the past and continues to happen in the present.

In this case, the action of finishing lunch happened at a specific point in time in the past, so the simple past tense is the correct tense to use.