In our school there_______ a library and three classroom buildings.
| A．is | B．are |
| C．has | D．have |
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
Remember not to ask ______ questions, like the age, when you talk with an American.
A. historical B. lifelong C. private
To the heavy traffic，1 have to leave so early．
A．increase B．avoid C．spread