大学英语：weaken: v 削弱、减弱，字根：weak: a 虚弱的

　　构词形式：adj/n + en或en + adj/n = v

　　Shorten, enlarge, enable, enrich, loosen, tighten etc.

　　2. nationwide: a 全国范围的，通过该词我们可以得到：worldwide:全世界范围的，regionwide, etc.

　　3.legal: a 合法的，反义词：illegal,不合法的;legalize: v 使…合法化。

　　The Netherlands became the first country to legalize euthanasia.

　　4. ensure: v 确保、担保，常见用法如下：

　　1). The police can ensure the witness from danger.

　　2). We can ensure that the work will be done in the right way.

　　5. oppose: v 反对、对抗;名词：opposition , 形容词：opposed

　　1). What he said was totally opposed to the facts.

　　2). Many people oppose building a new highway because of the great cost.

　　6. tradition: n 传统，由此可以联想到：

　　traditional: a; traditionally: ad; 反义词为：modern

　　1). _____ Chinese medicine is believed to be effective for many diseases.

　　2). It's important to keep up the fine ____ of plain living and hard work.

　　3). Christmas is ____ a holiday for a family to get together.

　　Answers: Traditional, tradition, traditionally

　　7. consideration: n 考虑、体谅、照顾，由此可以联想到：

　　Consider: v 考虑;considerate: a 体谅的，be considerate of; considerable: a 相当多的。请练习一下：

　　1). Losing 30 pounds changed her appearance _____.

　　2). It is very ____ of you to send me a birthday card.

　　3). The matter is receiving the serious ____ of the manager.

　　4). He left behind him a ____ amount of debt.

　　Answers: considerably, considerate, consideration, considerable