I want to be a teacher这里的want to be 为什么不写成want to do?给我讲讲

I want to be a teach of math 还是I want to be a teacher of math?为什么? I want to be a football player.Will he teach me how___better?I think so.I will___him. I want to fand a teacher to teach me english My English is poor.I want to get a t____ to teach English on weekend 英语翻译用I want to be a. 英语作文 i want to be a I want to be a gentle 英语翻译I want to be a mermaid I want to be a real I want to be a paintet是什么意思 I want to be a little boy. I want to be a winner是什么意思 Just be a person i want to I want to be a bad I don't want to be a i want to be a star I want to be a dancer是什么意思 I want to be a dancer是什么意思