Yingqi Bird Nest Library，the smallest library in the world，was opened to the public in Nanjing's Huashu Village ________ the World Reading Day this year．（ ）
A．onB．inC．atD．as
______ great fun Andrew has ______ DIY in the art room with his classmates!（ ）
A．What； doingB．What； done
C．How； doingD．How； done
Have you found the information about famous scientists _____ you can use for the report？
Not yet．I'll search some on the Internet．（ ）
A．whereB．whichC．whatD．who
I usually sleep with the window open _____ it's really cold．（ ）
A．ifB．becauseC．soD．unless
Aunt Li，who is the pretty girl in red in the picture？
It's my daughter．The picture ________ 10 years ago．（ ）
A．tookB．is takenC．has takenD．was taken
Doctor Ma is always careful with the operations．He often says"_____"．（ ）
A．A miss is as good as a mile
B．Many hands make light work
C．No pain，no gain
D．A friend in need is a friend indeed