1. 伯父;叔叔;舅舅;姑父;姨父
Someone's uncle is the brother of their mother or father, or the husband of their aunt.
e.g. My uncle was the mayor of Memphis...
我伯父是孟菲斯市市长。
e.g. A telegram from Uncle Fred arrived...
弗雷德舅舅发的一封电报来了。