36. The fifth generation computers, with artificial intelligence, ____and perfected now.
A. developed B. have developed
C. are being developed D. will have been developed
37. Hurry up, kids! The school bus ________ for us!
A. waits B. was waiting C. waited D. is waiting
38.The twins ______their homework, and then they were allowed to play badminton on the
A.will finish B. finish C. have finished D. had finished
39.Mr. Li is not at home. He _________ Shanghai.
A. has been in B. has been to C. has gone to D. have been to
40.She _______ to bed until she ________ her work.
A. didn’t go; had finished B. didn’t go; have finished
C. doesn’t go; had finished D. didn’t go; finished