ability n.能力，本領，能耐；專門技能。

（辨析）普通用詞，主要用于人，指在智力或體力上能夠做某事得實際能力，常后接動詞不定式或介詞in／for。

〔例證〕a player of great ability極有才華得球員She has the ability to run her father's business.她有能力經營父親得企業。

He shows an ability in／for farming.他顯示出農耕方面得才能。

capability n.能力，才能。

〔辯析〕尤指完成有難度得事情所需得能力，常后接動詞不定式或介詞of，可以復數形式出現。

〔例證〕manufacturing capability 生產能力

She has the capability to handle the work.她具備處理這項工作得能力，Mary has the capability of becoming an excellent teacher.

瑪麗有能力成為一名出色得教師。

In her opinion,simultaneous translation is beyond his capabilities.

她認為他做不了同聲傳譯。

capacity n.能力，才能；容納能力。

〔辨析〕指人理解或做某事得能力，或容器、房間等得容納能力，常后接介詞of／for。

〔例證〕a child's capacity for learning 孩子得學習能力

He has a capacity for computers.他具有操作計算機得能力。

The fuel tank has a capacity of 50 litres．這個油箱能裝50升油。

competence n.能力，勝任。

〔辨析〕強調做某事得非凡能力，常后接介詞in。

〔例證〕You should try to maintain your professional competence.

你應當盡力保持自己得可以能力。

We have doubt about his competence in teaching.

我們懷疑他教書得能力。

He demonstrated thorough competence in dealing with these issues.

他在處理這些問題時完全顯示出了他得能力。