Look! the ground is wet. It must have rained last night, _______?
Joy and Sorrow _____ next-door neighbours.
Ten minutes ______ a long time for one who waits.
E-mail, as well as telephones, ________ an important part in daily communication.
_____ you ready?
“Tom graduated from college at a very young age.” “He ______ have been an outstanding student.” a. must b. could c. should d. might