It's useful knowing several languages.为何用knowing不用to know

It's useful knowing several languages.为何用knowing不用to know It's useful(have) a good lifestyle For the students,it's useful to do more_____.(read) I think it's a.useful job.翻译 I think it's useful for the environment. Knowing how to ask for information politely is important,isn't it?What it's this It's been a pleasure knowing you.那个’s是has还是is还是was? Learning---------country's.language.is.a.betterway of knowing---------- culture.behind.It.添什么冠词 This is that we all think it's very important.A such useful information B so useful information It's not useful.You can throw it into the d_____ sometimes fire is useful,it's ()we must be ()wth it. 英语翻译Knowing lots of things is good,but knowing the limitationgs of one's knowledge is essential to using it peoperly. 我认为和他为此争吵没有用 I don't think it's useful ( )(我认为和他为此争吵没有用 I don't think it's useful ( )( )( )( )about this ______how to do it , we had to help him.A.His not knowing B. The boy knowing notC. He not knowing D. The boy's not having known请详细分析 This is _____ that all of us believe it’s very important.(2005年广州) A.such useful informationB.so useful an information C.so useful information D.such a useful information 给点建议 i find it's useful to learn English.为什么可以改成i find it useful to learn English呀?请说明理由.i find it useful to learn English.这种是什么句型? it's useful todo more() A read B reads C to read D reading说明理由 Because I think it's useful.I want to learn English[ ].补全对话