Sometimes we use noises rather than words to hesitate. Such hesitation varies from one language to another. In English, the sound 'en' or 'er' is used to hesitate. But if we overuse these sounds, we can sound very opposite to fluent. 
如果是經(jīng)常聽老外講話的人應(yīng)該會(huì)留意到，他們?cè)谥v話的時(shí)候有時(shí)候說"er",或者是拖長(zhǎng)某些音，這樣做的目的其實(shí)就是為自己贏得思考下面該說什么的時(shí)間。因此我們?cè)谡f英語的時(shí)候，也可以應(yīng)用這些技巧。

Like, er, you know…
These words don't have any meaning in themselves but they are very useful to make yourself sound more fluent and confident.
這些詞有時(shí)候本身不具有任何意義，但是如果使用正確，是很有幫助的，為你在交流中贏得思考的時(shí)間，并且聽起來也很地道。

But if you use them too much, you can actually sound very irritating.
大家要注意的是，如果你過度使用這些詞，就會(huì)讓人覺得很厭煩。

I think…
If I were you, I’d…
如果用I think...來表達(dá)自己的看法，但還不確定自己要具體說什么，就可以拖長(zhǎng)最后一個(gè)音。

^-^這些都是些小技巧，學(xué)會(huì)正確使用它們，會(huì)很有幫助。