As is well known, it is Hawking who the theory of black holes.
A, puts forward B, has put forward C, invented 
D, raised
I am really upset about tomorrow’s exam. I am always so slow.
_______! You can pass it. You have been working hard on it, haven’t you?
| A．Go ahead | B．Just feel at home | C．Are you kidding | D．Cheer up |
The heavy rain ______ us ______ going there.
| A．kept; 不填 | B．protected;from | C．prevented; from | D．forbade（禁止）; from |
No one can prevent the plan _____________.
| A．from carrying out | B．to carry out |
| C．being carried out | D．to be carried out |
It isn’t an excuse for your failure ___________ you didn’t know the rules
| A．That | B．Because | C．Why | D．How |
_____________ we all know is that destroying nature means destroying ourselves.
| A．what | B．Which | C．That | D．It |