Question

When he left/leaves the party, he waited for a taxi

Answer 1

When he left the party, he waited for a taxi

Answer 2

The sentence you provided is a bit unclear due to the combination of past and present tense. Let me break it down and provide explanations for both possible versions:

1. "When he left the party, he waited for a taxi." - In this sentence, "left" is in the past tense, and "waited" is also in the past tense. This means that the action of leaving the party and waiting for a taxi both happened in the past. The sentence describes a sequence of events where he left the party first and then waited for a taxi.

2. "When he leaves the party, he waits for a taxi." - In this sentence, "leaves" is in the present tense, and "waits" is also in the present tense. This means that the action of leaving the party and waiting for a taxi is a habitual or repeated action in the present. It suggests that whenever he leaves a party, he follows the habit of waiting for a taxi.

To choose the correct version, you should consider the context and whether the actions occurred in the past or if they are ongoing, habitual actions in the present.