Mr Green is my ______ .He's my mother's brother.急,求求各位朋友.请说明原因,要正确的答案.

Mr Green is my ______ .He's my mother's brother.
急,求求各位朋友.请说明原因,要正确的答案.

UNCLE 妈妈的哥哥或是弟弟,就是你的叔叔啊