3. "Why" is used to inquire about the reason or cause of something. In this case, the person is crying because they are upset.

4. "Where" is used to ask about the location or place where an action or event takes place. In this case, "They" usually spend their weekends in the country.

5. "When" is used to ask about the time or date of an event or action. In this case, Kate is going on holiday at the end of the month.

6. "What time" is used to ask about the specific time of an event or action. In this case, Paul finishes his work at 6.30.

7. "What" is used to inquire about the nature or specifics of something. In this case, he is studying English and Literature this term.

3. Why are you crying? 
4. Where do they usually spend their weekends?
5. When is Kate going on holiday?
6. What time does Paul finish his work? 
7. What is he studying this term?