The fifth generation computers, with artificial intelligence, _____ and perfected now.
| A．developed | B．have developed |
| C．are being developed | D．will have been developed |
The sight of the big cake on the table suddenly _________ me that it is my birthday today.
| A．remembers | B．impresses |
| C．confirms | D．reminds |
This produced a chain reaction, _______ made _______ possible for life to develop.
| A．what; that | B．which; it |
| C．when; that | D．how; it |
The thought they couldthe whole continent was exciting.
| A．that; cross | B．what; cross |
| C．whether; across | D．when; across |
_________ life will continue on the earth for millions of years to come will depend on __________ this problem can be solved.
| A．If; that | B．Whether; if |
| C．If; whether | D．Whether; whether |
--May I open the window to let in some fresh air?
-- __________
| A．Come on. | B．Take care. |
| C．Go ahead! | D．Hold on! |