16. Einstein，the famous scientist，was born ____________ March，1879.
A. at B. on C. in D. to
17. Money is important ____________ it’s not the most important thing.
A. and B. but C. or D. so
18. My sister has two skirts. One is yellow，and____________ is black.
A. other B. another C. others D. the other
19. Lee came to Beijing in 2005.He has been here ____________ than you.
A. long B. longer C. longest D. the longest
20. There ____________ many students in the library after school every day.
A. has B. have C. is D. are