Choose the appropriate verb form to complete the sentence. If the manager…

Concept. A conditional sentence that imagines a past situation as different from what actually happened uses the past perfect (had + past participle) in the if-clause and a perfect modal (would / could / might + have + past participle) in the main clause. The past perfect marks the condition as earlier in time and unfulfilled; the perfect modal marks the result that therefore never came about. The two halves are a fixed pair: both encode the same unreal past time, so the form in one half is fixed by the form in the other.

Application. Work from the half of the sentence that is already given.

1. Isolate the main clause: we might have avoided the delay.

2. Analyse its form: might (modal) + have + avoided (past participle). That is the unreal-past result pattern.

3. Match the if-clause to it: the condition half of that pattern is written as had + past participle.

4. Apply it to the verb address, whose past participle is addressed. The blank therefore takes had addressed.

5. Confirm with the time adverb earlier, which places the condition before the past result — exactly the anteriority the past perfect encodes.

Cross-check the other forms. Each rejected form would force a different main clause:

• addressed (simple past) sets up an unreal present or future condition, whose main clause takes a bare infinitive after the modal: If the manager addressed the issue earlier, we might avoid the delay.

• address and addresses (base form and third person singular) set up an open, real condition, whose main clause takes will or may plus a bare infinitive: If the manager addresses the issue earlier, we may avoid the delay.

• None of those three can stand beside might have avoided, because a perfect modal in the main clause admits only the past perfect in the if-clause.

Result. If the manager had addressed the issue earlier, we might have avoided the delay.