It is hard to say what kind of person he is. Sometimes he is
| It is hard to say what kind of person he is. Sometimes he is very friendly; at other times he ___ be very cold. |
| [ ] |
| A. can B. must C. will D. shall |
可能相似的问题
| It is hard to say what kind of person he is. Sometimes he is very friendly; at other times he ___ be very cold. |
| [ ] |
| A. can B. must C. will D. shall |