(1) condescend to表示①以高人一等的态度对待(某人)；屈尊、放下架子(做某事)；②贬损人格做(某种坏事)。

• A teacher should never make the mistake of condescending to children.
  一个教师永远不应犯下贬抑孩子人格的错误。
• He doesn't like being condescended to .
  他不喜欢被别人以高人一等的态度来对待。
• I'm really surprised at you, condescending to such tricks!
  我真对你感到吃惊，居然堕落到搞这种伎俩！
• He had to condescend to (do) hack work in order to keep the wolf from the door.
  为了维持温饱，他不得不屈尊受雇于人。

③在表示“屈尊(做某事)，贬损人格做(某种坏事)”时，condescend也可接不定式。

• That woman is so proud that she will not condescend to speak to her neighbors.
  那女子非常高傲，不肯放下架子跟邻居讲话。
• He went so far as to condescend to take bribes.
  他竟然堕落到接受贿赂。

 (2) demean oneself表示①(行为举止的)表现；②自贬身份(做某坏事)，后接by doing。

• How did my son demean himself in the presence of the King?
  我儿子在国王面前表现怎么样？
• Never demean yourself by taking money as a reward for doing something wrong.
  决不要以接受做某种错事的酬金来贬低你自己。

 (3) descend to也可表示“堕落到(做某坏事)的程度”，to为介词，后接名词、动名词。

• If a prisoner is badly treated, he may descend to violence .
  如果囚犯受到虐待，他可能会动用暴力。
• I'm surprised that you would descend to lying .
  我很感吃惊，你竟然堕落至撒谎的地步。

 (4) lower oneself是“降格或失身份去做(某种不好的事)”，后可接不定式，也可接介词by或to引导的短语。

• Good-mannered people would not lower themselves to be so rude.
  有礼貌的人是不至于将自己降格到如此粗鲁的地步的。
• You would be lowering yourself if you did that.
  你如那样做，就会失去你的身份。
• He would never lower himself by/to taking bribes.
  他从不肯接受贿赂贬损自己。

 (5) sink to除其他意思外，也可表示“堕落到(做某坏事)的地步”，to为介词。

• I am ashamed to learn that you would sink to such depths of behavior.
  听说你竟堕落到做出这种行为的地步，我感到羞耻。
• I did not think that you would sink to cheating.
  我认为你不会堕落到欺诈的地步。

 (6) stoop to可表示①向……俯下身/弯下腰；②屈尊、降格、失身份(做某事)，to 为介词。可用于贬义，也可用于褒义。

• I had to stoop to the child's height to hear what he was saying.
  我得俯身到那个小孩的高度，去听他在说什么。
• I'm surprised that you would stoop to such behavior!
  我感到吃惊，你会失身份做出这种行为！
• I didn't imagine that he would stoop to cheating.
  我想象不出他会不顾身份进行欺诈。