Complete the sentences with "in," "on," "last," or "ago."

1. What did you do on Saturday?
2. Did he say he was born in 1950?
3. What did you study last week?
4. He phoned me half an hour ago.
5. What time did you get home last night?
6. Can you go on holiday in July?
7. Her birthday is on 10th February.
8. I finished class ten minutes ago.
9. Did you go to the cinema last weekend?

To complete the sentences with the correct prepositions and time expressions, we need to understand each sentence's context regarding timing and events:

On - Saturday is referred to as a specific day of the week. We typically use 'on' when talking about days and dates.
In - When mentioning a specific year, we use 'in' to indicate the period of time.
Last - To refer to the week that has just passed, we use 'last'.
Ago - 'Ago' is used to describe time intervals from the present going back into the past.
Last - For the night that has just passed, we use 'last'.
In - For months, we use 'in' as it refers to a broader time frame within the year.
On - When we talk about specific dates, we use 'on'.
Ago - To describe a specific duration from the past to the present time, 'ago' is the correct term.
Last - Referring to the past weekend, 'last' is used to describe the immediate prior weekend.

These prepositions and expressions help provide clarity in specifying times and dates when narrating events or describing periods.