1. Good books _ again and again.A. should be readedB. should be readC. must readD. ought to read2. The children _ by the nurse.A. were lookedB. looked afterC. were looked afterD. looked3. He _ some pieces of advice, but he _ to them.A. gave, didnt listenB. was given, wasnt listenedC. give, wasnt listenedD. was given, didnt listen4. When_ the accident _ ?A. was, happenB. did, happenC. is, happenD. was, happened