Our home river, Yitong River used to __________ seriously, but now it's as clear as a mirror.
A.pollute B.polluting C.is polluted D.be polluted
It's too hot in summer. Some people like to sleep with their windows __________.
A.open B.opened C.opening D.to open
It's really lucky that Peter won a great prize __________ a free journey to Japan.
A.except B.against C.without D.including
Tom made a model plane __________ he could help his friends learn science.
A.if B.so that C.because D.even if
There __________ some yogurt and bananas in the fridge. Let's make a banana milk shake.
A.is B.are C.was D.were
My brother is good at playing __________ chess. I've learned a lot of skills from him.
A.the B.a C.an D./
