【正文】
_______ in a cool place in summer.A. must keep B. mustn’t keep C. must be kept D. mustn’t be kept father ________ to work in Hong Kong 3 years ago.A. sent B. was sent C. has sent D. has been sent pen ________ well.A. writes B. is written C. was written D. writing changes ________ in the town since 1988.A. have taken place B. have been taken placeC. has taken place D. has been taken place positions must ________ next Monday.A. be hand in B. be handed in C. handed in D. be handing in child will ________ back to his parents next month.A. sent B. send C. be sent D. be sending his work ________ yet?A. have…been finished B. has …been f