find and correct the mistake :
1. these pills should be take every fou hours.
--> taken
2 they were questioning by the police
--> questioned 
3 the letter should been delivered in the afternoon
--> be
4 the bell was rung for several times
--> has been rung

1. These pills should be take=> TAKEN every four hours
2. They were questioning=> QUESTIONED by the police
3. The letter should been=> BE delivered in the afternoon
4. The bell was rang=> HAS RUNG several times
_vô trang mình 5 sao nha_