Every day students in our school will do outdoor activities ______ there is a heavy haze(雾霾).

He didn’t listen to the teacher carefully in class.______, he couldn’t pass the exam.

Sherry _______ France many times, so she is very familiar with its capital city, Paris.

As far as I am concerned, a good plan must be ______ so that it can adapt to some necessary changes.

apples do you want to buy— Ten, please. And are they