1. 疲惫;疲劳;疲倦
    Fatigue is a feeling of extreme physical or mental tiredness.

    e.g. She continued to have severe stomach cramps, aches, fatigue, and depression...
           她仍然患有严重的胃痉挛，感觉疼痛、疲乏、抑郁。
    e.g. Clarke says his team could have lasted another 15 days before fatigue would have begun to take a toll.
           克拉克说，他的团队本来还可以再坚持 15 天，只是疲劳可能会造成严重后果，只好作罢。

2. 疲劳;厌倦
    You can say that people are suffering from a particular kind of fatigue when they have been doing something for a long time and feel they can no longer continue to do it.

    e.g. ...compassion fatigue caused by endless TV and celebrity appeals.
           没完没了的电视节目和名人呼吁而导致的同情心疲劳
    e.g. ...the result of four months of battle fatigue.
           4 个月的战斗疲劳带来的后果

3. (士兵的)作训服，工作服
    Fatigues are clothes that soldiers wear when they are fighting or when they are doing routine jobs.

    e.g. He never expected to return home wearing US combat fatigues.
           他从没想到会穿着美国军服回家。

4. (金属或木材的)疲劳
    Fatigue in metal or wood is a weakness in it that is caused by repeated stress. Fatigue can cause the metal or wood to break.

    e.g. The problem turned out to be metal fatigue in the fuselage.
           问题原来是飞机机身出现金属疲劳。