We must_______that our customs and habits are different from theirs. A: keep up with B: bring forward C: keep in mind D: come true

Themedicine（）cool,cleananddry. A: must  keep B: must  be  kept C: must  be  keep D: must  be  in

The flowers ( ) every day. A: must be water B: must be watered C: must watered D: must water

Such films _____ by children like you. A: must be not seen B: must not be see C: must not seen D: must not be seen

These books ______ good care of. A: must taken B: must take C: must to take D: must be taken

The medicine （） cool, clean and dry. A: must keep B: must be kept C: must be keep D: must be i

The flowers （） often. A: must be water B: must be watered C: must watered

Old people () carefully. A: must be listened B: must be listened to C: must listen to

He looks tired. He ______ a sleepless night. A: must have been B: must have had C: must be D: must have

The construction of the laboratory ________ by the end of July. A: must be completing B: must complete C: must have complete D: must have been completed