it's not polite to laugh at others这里的to laugh是什么成分

it's not polite to laugh at others这里的to laugh是什么成分 laugh at等于It's not polite to laugh at others.It's not polite It is not polite to laugh（） others It's not good to ________ others .A.laugh at B.shout at C.po It's impolite______ you to laugh at others to laugh at others is is___wrong to laugh at others It is not polite. laugh at people they did not want others to laugh at their daughter 这里did no 英语翻译Some small children dont't know it's not polite to laugh 英语翻译Some small children don't know it's not polite to laugh it's impolite to laugh at ( ) disabled