What are some common prepositions used in expressing time and frequency?

Some common prepositions used in expressing time and frequency are:

1. At: Used to indicate a specific point in time. For example, "I have a meeting at 9 am."

2. In: Used to indicate a general period of time. For example, "I will finish the project in a week."

3. On: Used to indicate specific days or dates. For example, "I have a doctor's appointment on Monday."

4. During: Used to indicate a period of time within a larger time frame. For example, "I studied during the summer break."

5. For: Used to indicate the duration of an action or event. For example, "I have been waiting for an hour."

6. Since: Used to indicate the starting point of an action or event. For example, "I have been working here since 2010."

7. From: Used to indicate the starting point of an action or event. For example, "I will be on vacation from Monday."

8. To: Used to indicate the ending point of an action or event. For example, "The concert will take place from 7 pm to 10 pm."

9. By: Used to indicate a deadline or the latest time something should be done. For example, "Please submit your report by Friday."

10. Throughout: Used to indicate the entire duration of an action or event. For example, "I will be busy throughout the day."

These are just a few examples of common prepositions used in expressing time and frequency. It is important to note that prepositions can vary depending on the context and the specific time or frequency being referred to.