A.can; must | B.can't; must | C.mustn't; can | D.can; mustn't |
A.can; must | B.must; mustn't | C.may; must | D.must; may |
A.The light is red. You can cross the street. | B.The light is red. You must cross the street. |
C.The light is red. You mustn't cross the street. |
A.You mustn’t cross the street. |
B.You must take the medicine. |
C.You mustn’t talk in the library. |
A.study hard | B.hard study |