Đề của bạn có một chút vấn đề nên mình đã sửa rồi nhé!

1:i spent two hours doing my homework

=>It took me 2 hours to do my homework.

2: English is a compulsory second language in all secondary schools in Vietnam

=>Students in all secondary schools in Vietnam have to use English as a second language.

3:i don't like going to school on Saturdays

=>I wish I didn't have to go to school on Saturdays

4:you must clean this machine every time you use it

=>This machine must be cleaned every time you use it.

1. It took me two hours to do my homework

( it takes someone to do sth)

2. Students have to learn English as a compulsory second language in all secondary schools in Vietnam

( đề thiếu verb sau have to nên a thêm learn vào nha, as : như )

3. I wish I didn't go to school on Saturdays

( đây là wish ở hiện tại : S + wish + S + V2/ed.)
4. This machine must be cleaned everytime you use it

( bị động và sửa every thành everytime, every ko có nghĩa )