某课外研究性化学兴趣小组查阅资料：硫酸铜受热分解生成氧化铜和气体，受热温度不同，该
气体成分也不同，气体成分可能含
、
和
中的一种、两种或三种。下列叙述中错误的是（ ）
| A．所得气体成分只有一种，则气体为 |
| B．所得气体成分有两种，则气体为、 |
| C．所得气体成分有三种，则气体为、和 |
| D．若发现气体成分中有，则该气体中一定含有 |
If you leave the club, you will not be_____back in .
| A．received | B．admitted | C．turned | D．moved |
What I need is_____ book that contains ______ABC of oil painting.
| A．a; 不填 | B．the; 不填 | C．the; an | D．a ; the |
Jenny nearly missed the flight______ doing too much shopping.
| A．as a result of | B．on top of | C．in front of | D．in need of |
The CDs are on sale! Buy one and you get ______ completely free.
| A．other | B．others | C．one | D．ones ks |
Progress______ so far very good and we are sure that the work will be finished on time.
| A．was | B．had been | C．has been | D．will be |