The top students believe being careful is the ______ to good scores on their exams.
A. secret B. form C.process
It’s reported that Tu Youyou won the Nobel Prize. We ______ her.
A. are surprised at
B. are known for
C. are proud of
The book Expo(书博会) ______ in September this year. It encouraged people to read.
A. is held B. was held C. will be held
---______ can we warn people not to swim here?
---By putting up signs.
A. How B. Why C. Where
---I saw the 3D printer print some cartoon characters at the science fair.
---Sounds fun! I believe such technology will be ______ used in many ways
A.widely B. difficultly C. clearly