As is well known, carelessness and irresponsibility _______ many deadly accidents.
| A．lead to | B．result from | C．contribute to | D．result in |
Obama says he is angry about policies that always favor the wealthy and powerful over ______ Americans and insists that opportunities be opened up to all.
| A．average | B．intelligent | C．competitive | D．Original |
It is required that all traffic participants should __ the traffic rules to make traffic safer and faster.
| A．perform | B．possess | C．observe | D．Support |
______ it is true that a student’s most important goal is to do well in his or her studies, it doesn’t need to be the only goal.
| A．When | B．As | C．While | D．Before |
Johnson was much depressed as he didn’t sell half as many computers as he thought he____.
| A．will | B．did | C．was | D．Would |
----What ______ do you focus on when choosing a mobile phone for personal use?
----Its functions and stand-by time.
| A．features | B．signs | C．symbols | D．Brands |