Sure! Here are the full sentences based on the provided prompts:

1. The test is not as difficult as I think.
2. She is the most beautiful girl in your school.
3. It is necessary to study the history of the Temple of Literature.
4. I am going to take a day off next week.
5. Our class will have a picnic in the countryside tomorrow morning.
6. Robots do all the housework and take care of our family future.
7. My students are good at speaking and writing English.
8. Phuc wants to listen and speak English well.
9. My brother prefers to watch cartoons instead of listening to music.
10. They have known each other for 3 months.
11. Nam's teacher teaches him since he came here.
12. We did not go on a picnic since COVID-19 started.
13. Which place have you been to since you left school?
14. Yesterday, Peter answered the questions most quickly in my class.
15. He studied hard, so he got good marks.
16. She was sad because she got a bad mark yesterday.