职称英语考试基础词汇重点解析71

作主语补足语

带有宾语补足语的谓语动词变为被动语态时，宾语成了主语，宾语补足语也就相应地成为主语补足语。当动词不定式用作主语补足语时，一律要用带“to”的形式。如：

Their children are allowed to make their own decisions.

允许他们的孩子自己拿主意。

The elephant was made to dance before audience.

使大象在观众前跳舞。

不定式结构在英语文章中使用频率较高, 如下面的这段文字中(4个句子), 不定式结构出现了5次, 请大家确认这些不定式结构在句子中的语能.

（1）So far there is no data to suggest that people living on metal-rich soils experience a potential health hazard. (2) They are also the most likely ones to eat potentially dangerous metal-rich soil. (3) Some trace metals are alleged to cause cancer and also known to cause poisoning中毒. (4) There is a vital need to understand the potential risks and long-term health effects of living on naturally contaminated soils.

提示: 相邻语句往往围绕同一中心发展, 在词语上常常表现为: 相邻语句中出现呼应的词语.

分析：第1，2，4句中不定式是作定语；第3句的不定式是作主补；

(hazard –danger 危险)

(hazardous – dangerous危险的)

(contaminate - pollute污染)