We are confident that the environment ________ by our further efforts to reduce pollution.
A．had been improved B．will be improved
C．is improved D．was improved
He was unhappy when he sold his guitar. After all，he________it for a very long time.
A．has had B．had had
C．has D．had
Hurry up，kids! The school bus ________ for us!
A. waits B. was waiting
C. waited D. is waiting
The water supply has been cut off temporarily because the workers ________ one of the main pipes.
A. had repaired B. have repaired
C．repaired D．are repairing
We ________ very early so we packed the night before.
A. leave B. had left
C. were leaving D．have left
I felt very tired when I got home.and I ________ straight to bed.
A．go B．went
C．had gone D．have gone
