請問說一個人"無能"的英文怎樣寫?

incompetentADJ-GRADED 能被表示程度的副词或介词词组修饰的形容词無能力的;不稱職的;不合格的 If you describe someone as incompetent,you are criticizing them because they are unable to do their job or a taskproperlyadj. 無能力的； 不勝任的； 不適當的 n. 無能者； 不勝任者 He is utterly incompetentat his job. 他完全不能勝任他的工作。his incompetent handling of the affair 更多牛津 他在處理這件事上的無能表現 impotencen. 無能為力； [醫]陽痿； 陰痿

(1)Incompetent adj opp. competent:-He is an incompetent worker, hopeless+useless.
---Incompetence n :-eg:-His incompetence in working disqualified him.
(2)Impotent adj :-eg:-impotent to her=feeble in sex;
---Impotence n (sterility) eg:-His impotence to her made him despair.

無能==Incapability; He is incapable of doing anything.
性無能==Impotence;( sterility不能生育)

These are two common sets of words: Incompetent 無能、不稱職 (adj.); Incompetence (n.) impotent 性無能 (adj.); Impotence (n.)不要用此代替上述之incompetent