「飲み過ぎ」はdrink too muchとなります。
Why don't you stop drinking too much?
「～やめといたら？」はWhy don't you stop ～ing?というパターンです。
stopの後に動名詞を使います。
この表現は強く注意したい時に使えます。
How about not drinking too much?
(How about you not drink too much?もいいます。)
「～したらどう？」というのは、How about ～?というパターンです。
これは上記よりソフトな言い方です。
1. The function here is to give your opinion
2. The function here is to make a suggestion to go home.
3. The function here is to offer an alternative drink which may help to negate the effects of alcohol already drunk. This phrase is also a well-known euphemism for: 'I think you're drinking too much.'
Your drinking habits are becoming bad and I think you should calm down.
>It's time to calm down on the drinking.
This sentence can be used when you and your friend are out for drinks and he is busy getting drunk.
>I think you had enough to drink for tonight.
This sentence can be used when you and your friend are out for drinks and he is busy getting drunk.
>Your drinking habits are becoming bad and I think you should calm down.
This sentence can be used when you feel your friend is drinking to much in general.
It's time to calm down on the drinking.
友達と飲みに行った時に友達が飲み過ぎたときに使える表現です。
I think you had enough to drink for tonight.
友達と飲みに行った時に友達が飲み過ぎたときに使える表現です。
Your drinking habits are becoming bad and I think you should calm down.
友達が飲み過ぎたときに感じた時に一般的に使える表現です。
I think you've had too much to drink and need to stop.
I think you have reached your limit for tonight and should stop drinking.
You are drunk already and should stop drinking.
"I think you've had too much to drink and need to stop." lets someone you know that you think that they have drank enough alcohol and it would be best if they stopped drinking now.
"I think you've had too much to drink and need to stop."
(私はあなたがお酒を飲みすぎたのでこれ以上飲むのをやめたほうが良いと思います)
これはあなたがその人がお酒を十分に飲んだと思っていることとお酒を飲むことを今やめたほうがよいと思っていることを知らせます。
"I think you've reached your limit for tonight."
This is letting them know that they have had enough to drink for the night and should probably stop.
"Let's get some water."
It's a way to get them to stop drinking while also not addressing that they had too much to drink. Sometimes it can be a tough situation to be in, this helps you avoid being uncomfortable while getting them to stop drinking alcohol.
"I think you've reached your limit for tonight."
(あなたは今晩の限界に達したと思います)
これは彼らにその夜十分にお酒を飲んだこととおそらくそれ以上飲むのをやめたほうがよいであろうことを知らせています。
"Let's get some water."
(水を飲みましょう)
これは彼らが飲みすぎたことを指さずに飲むのをやめさせる方法です。
時に難しい状況ですが、これは不快に感じることを避けながら彼らがお酒を飲むのをやめさせることを助けてくれます。
アメリカ合衆国 
日本 
イギリス 
南アフリカ 
