— What great trouble I have solving this problem now！
—_____ my advice, you ________less trouble.
| A．If you had taken, would have had | B．If you took, would have |
| C．If you had taken, would have | D．If you take, will have |
Kevin was not good at Chinese at first. After two months in China, _____, he made great progress.
| A．while | B．but | C．however | D．otherwise |
The worst tornado of all time occurred in 1925, ______ three US states.
| A．affected | B．affecting | C．to affect | D．affects |
______ right in the center of the city, the park attracts a lot of tourists.
| A．Seating | B．Laid | C．Situated | D．Stood |
Physics ________ my favorite subject. I like it so much that I wish we had a physics class every day.
| A．is | B．are | C．was | D．have been |
Good care must ______ these children, especially when they are ill.
| A．take | B．be taken | C．take of | D．be taken of |