I saw Jim ______ into that new building just now．
Oh，it's our new library．It ______ to the public for a week．（ ）
| A． |
walk； has opened |
| B． |
walk； has been open |
| C． |
walking； has opened |
It's not __________ to be friendly． You have to be a friend． Go and talk to Sam．（ ）
A．good enoughB．late enough
C．too goodD．too late
He stayed up very late that night． __________ he woke up in the morning， the sun was already high up in the sky．（ ）
A．UntilB．AfterC．WhileD．As
It's said that drinking coffee __________ cancer． Do I have to give it up？
Relax! Not everything on Wechat is true． In fact， a coffee a day keeps the doctor away．（ ）
A．causesB．has causedC．causedD．had caused
You're the future of this country． Don't keep asking what this country can do for you． Ask_________ what you can do for this country．（ ）
A．usB．ourselvesC．youD．yourselves
I'm planning to climb Mount Huang this summer． Would you like to come along？
Wow! That would be exciting __________ challenging． I'm in!（ ）
A．as well asB．as good asC．as long asD．as far as