Mary____ a math problem with her classmates when the math teacher knocked at the classroom door．（ ）
| A． |
has discussed |
B． |
was discussed |
| C． |
was discussing |
D． |
discusses |
Would you like another cup of coffee，Linda？
Thank you anyway．I've already had one cup，and I'm drinking _______ cup．（ ）
A．oneB．the firstC．the secondD．the third
Do American students also have lots of_______ to do？
Sure．But they do fewer memorizing exercises．（ ）
A．sportsB．surveysC．homeworkD．housework
_______the scientists' hard work，Tiangong II was launched（发射）successfully．（ ）
A．As forB．Thanks to
C．Instead ofD．According to
In Switzerland，keeping only one goldfish isn't _______，because the government believe it is very bad to make such social animals live alone．（ ）
A．stoppedB．doubtedC．refusedD．allowed
A little monkey might feel sad because of having a new baby sister or brother!
Yeah．I didn't know that _______ I saw the film Born in China．（ ）
A．ifB．untilC．sinceD．although