it's necessary to know different (customs) of sending gifts in different countriescustom在这句话中的意思是什么,为什么加s

It's necessary to learn English well. 翻译it's not necessary to hurry I find it necessary to know more about other countriesit necessary 不应该是it's necessary. it's necessary for you to give up smoking(保持句子原意) it's necessary ____you____smoke it's necessary是什么意思 i think it's necessary to be friendly to others 的necessary用什么形式 it's not necessary to be the same翻译 翻译：It's not necessary to be the same. It's not necessary to the same.这句改错 it's not necessary to be the same 英语翻译It's necessary for us to have a meeting. it's necessary for us to have healthy eating habits it's necessary for us to have healthy eating It's quite necessary to _______ ________ ________ _______ It's necessary to visit him.同义句转换 It's necessary for sb.to do.(中文意思） 应该是It's necessary for keep fit.为什么正确答案确是It's necessary to keep fit. I thought____us students to have plenty of exercise every day.A.It's necessary to B.it necessary for C.it necessary of D.it's necessary of请教选什么为什么