1. A serious road accident happened while we were waiting for the bus yesterday. (while)

S+ Ved/cột 2+ while+ S+ was/were+ Ving?

2. I had to get the mop since I spilled my juice

because/as/since+ clause: bởi vì

3. He fell down the ladder and his leg was broken. 

S+ Vqkđ+ adnd+ S+ Vqkđ

4. We had picked up trash before leaving the campsite

S+ had P2+ before+ Ving

5. It started raining when they were putting up the tent.

hđ đang diễn ra có 1 hđ khác xen vào=> qktd: S+ was/were+ Ving

6. I will go out with my friends after I get my parents' permission

S+ will V+ after+ S+ Vhtđ

7. The weather was bad when We were on holiday last month

S+ Vqkđ when+ S+ Vqkđ

8. I will call my mom as soon as I get the result

S+ will V+ as soon as + S+ Vhtđ

9. My father usually drives me to school when it rains

S+ vhtđ when+ S+ Vhtđ

10. Jack can't play games before He finishes his homework

S+ can't + V+ before+ S+ Vhtđ