–Were you at school when he came to see you?
–Yes, I ______ a math class.
A. was having B. had C. am having
If there no buying and selling of animals, there no killing in nature.
A. is; will be B. will be; will be C. is; is
We can do a lot to stay healthy. , we should eat a balanced diet.
A. At a time B. In fact C. First of all
I can’t afford the car, five thousand dollars ______ too much for me.
A. is B. are C. be
– Will you please go to see the movie Guanyinshan with me?
– No, I won’t. I it already.
A. saw B. have seen C. see
As everyone knows, rubbish everywhere.
A. need be thrown
B. mustn’t be thrown
C. can’t throw
