What are the functions of time clauses? Provide examples.

Time clauses are used to indicate when an action or event takes place in relation to another action or event. They provide information about the timing or duration of an action. Here are some examples of the functions of time clauses:

1. Indicating a specific point in time:
- I will call you when I arrive home.
- She always goes for a walk after she finishes work.

2. Expressing a duration of time:
- He studied for three hours before the exam.
- They had been waiting for an hour when the bus finally arrived.

3. Showing a sequence of events:
- After she woke up, she brushed her teeth and had breakfast.
- Once he finished his work, he went out for a walk.

4. Describing a repeated action:
- Every time it rains, she stays indoors.
- Whenever he visits, we go out for dinner.

5. Expressing a condition or contingency:
- If it snows tomorrow, we will go skiing.
- Unless you finish your homework, you cannot go out to play.

6. Indicating a future action or event:
- I will call you as soon as I get the information.
- We can go to the park once it stops raining.

These examples demonstrate the various functions of time clauses in providing information about the timing, duration, sequence, condition, and future actions or events.