It has been accepted that all the students ____ put on masks before going to school in case they are infected with flu virus.
| A．shall | B．will |
| C．need | D．may |
Having an outdoor meal is always fun, but it can also be disappointing if ________.
| A．planned not carefully | B．not planning carefully |
| C．not planned carefully | D．not to be planned carefully |
You will succeed in the end ________ you give up halfway.
| A．even if | B．as though |
| C．as long as | D．unless |
Not until the train pulled into the next station _______her suitcase gone.
| A．Mary had found | B．had Mary found |
| C．did Mary find | D．Mary found |
The heavy fog in London made _______deep impression on us, which was sometimes so heavy that we lost ________sight of everything.
| A．a; the | B．a; 不填 |
| C．the; a | D．the; 不填 |
Thegovernmentshouldprotecttheoldvaluablebuildings____theyarenotin
harmonywiththemodernonesnearby．
| A．eventhough | B．asif |
| C．evenso | D．nowthat |