当你想要给出非常强烈的建议，甚至带点威胁含义的时候，可以使用以下三个句型：
You'd better not do this.
你最好别这么做。
You don't want to do this.
你不会想要这么做的。
I wouldn't do that if I were you.
如果我是你我就不会这么做。

例句：
Hey, I wouldn't do that if I were you. There is a fine you would have to pay.
嘿，如果我是你我就不会这么做。你会被罚款的。
You'd better not do that or I am going to hit you on the head!
你最好别这么做，不然我这一拳就会砸在你的脑袋上。
You don't want to do that or the police will come and arrest you.
你最好别这么做，不然警察会来抓你的。

当你想要适当给出友好建议时，以下四点技巧以及相关句型可以参考：
1.Use a modal verb 使用情态动词
句型：should do sth/ought to do sth 应该做某事
Hey, you should drink less coffee. It makes you jumpy.
诶，少喝点咖啡啦。喝太多你会紧张坐立不安。
Hey, you ought to go out more if you are lonely.
诶你要是觉得孤单，就多出去走走。

2.Make it into a question to make advice less direct 使用问句的形式让建议听起来更委婉
句型：Why not do sth?/Why don't you do sth?/How about doing sth? 何不这么做呢？这么做如何呢？
Why don't you start learning to be patient Cara?
卡拉，何不学着耐心一点呢？
How about doing some more exercises Day?
Day，多做点运动如何呢？

3.Put yourself in the person's position 换位思考
句型：If I were you,... 如果我是你的话，...
Hey if I were you I would ask her out, she looks into you.
如果我是你的话我就会约她出来，她看起来很喜欢你。

4.Make a suggestion 使用 suggest/recommend 等建议句型
句型：I would suggest doing sth./I would recommend you to do sth.
I would suggest doing more exercise.
我会建议多做运动。
I would recommend you to watch yourself around her.
我建议你在她面前谨言慎行一点。