9. Nam attends the activity. He needs to improve his social skills.
→ Because Nam needs to improve his social skills, he attends the activity
10. The river is too dirty for us to swim.
→ Since the river is too dirty, we can't swim
→ Because / Since + clause : Bởi vì ...
CHÚC BẠN HỌC TỐT!
Cho mk xin ctlhn nha! Thanks nhìu!