How does agreement work with time clauses?

Agreement with time clauses depends on whether the time clause is referring to the present, past, or future.

1. Present time clauses: When the time clause refers to the present, we use the present tense in the main clause. For example: "If she is late, we will start without her." Here, the present tense "is" in the time clause agrees with the future tense "will start" in the main clause.

2. Past time clauses: When the time clause refers to the past, we use the past perfect tense in the main clause. For example: "If she had arrived earlier, we would have waited for her." Here, the past perfect tense "had arrived" in the time clause agrees with the conditional past tense "would have waited" in the main clause.

3. Future time clauses: When the time clause refers to the future, we use the present tense in the main clause. For example: "If it rains tomorrow, we will stay indoors." Here, the present tense "rains" in the time clause agrees with the future tense "will stay" in the main clause.

In summary, agreement with time clauses is based on the tense used in both the time clause and the main clause, ensuring that they are consistent and coherent.