1. By keeping their pupils working unnecessarily long at some little part of the subject, they often weaken their interest in learning the language.
    让学生们在一些细小的方面花去过多的时间反复练习，这往往会减弱他们学习语言的兴趣。

2. The king tried to weaken the power of the clergy.
    国王试图削弱教会的权力。

3. The study's ultimate aim, he says, is to "weaken conventional notions of race" that cause racial prejudice.
    他说研究的最终目的是"削弱"造成种族偏见的"传统的种族观念"。

4. Parents sometimes weaken the process by taking the forms and filling in false and wishful data about their children's habits, especially on the smoking question.
    有时家长会拿走表格，填入不真实的、一厢情愿的数据来反映他们孩子的习惯，特别是在吸烟问题上，这就削弱了这种做法的作用。