1. (大学、教会、银行等)(大型)机构
    An institution is a large important organization such as a university, church, or bank.

    e.g. ...the Institution of Civil Engineers...
           土木工程学院
    e.g. Class size varies from one type of institution to another...
           班级大小因院校类型而异。

2. (精神病院、孤儿院等)社会收容机构
    An institution is a building where certain people are looked after, for example people who are mentally ill or children who have no parents.

    e.g. He was transferred to Shoal Creek Mental Institution for an indefinite period...
           他被转到了肖尔溪精神病院，要在那里无限期地呆下去。
    e.g. Larry has been in an institution since he was four...
           拉里从4岁起就一直生活在孤儿院。

3. 习俗;制度
    An institution is a custom or system that is considered an important or typical feature of a particular society or group, usually because it has existed for a long time.

    e.g. I believe in the institution of marriage.
           我相信婚姻制度。
    e.g. ...the institution of the family.
           家庭制度

4. 建立;设立;制定
    The institution of a new system is the act of starting it or bringing it in.

    e.g. There was never an official institution of censorship in Albania.
           在阿尔巴尼亚从未设立过官方审查制度。
    e.g. ...the institution of the forty-hour week.
           每周 40 小时工作制的建立