—Does Liu Hui serve in the army? —No, but he ________ in the army for three years. 

 The suit _____ over60 dollars.

．— What terrible weather! It  ________  for ten days, more or less.— The rain season will last about a month.

— Can you come to my birthday party tonight? — I’d love to, but I______ on a patient at 6 o’clock.

I first met Mr. Smith in America. He ______ at Stanford University then.