16. I had ______ feeling of happiness when I heard that he had made ______ great progress.
A. a; a B. the; a C. the; 不填 D. a; 不填
17. It is known to us all that the People’s Republic of China ______ on October 1, 1949.
A. was founded B. was found C. is founded D. is found
18. I have been looking for my lost cat for three days, but I still ______ it.
A. didn’t find B. don’t find C. hadn’t found D. haven’t found
