1.) There's still some alcohol in my system. (まだ酒が残っている) 「酒を飲んで数時間しか寝てないからまだ酒が残っている」は英語でThere's still some alcohol in my systemと言えます。普通はお酒を飲んでいる時はこの文を言いませんが、言ったらきっと相手が理解できます。お酒を飲んでいる時は体の中で酒があるかどうかはあまり気にしないんです。
The two sentences you see provided above are great ways to express to your listener that you still feel like you have some alcohol in your system. In the first sentence you will see the word buzz. If someone has a buzz that means they feel a slight effect of alcohol in their system. This word is appropriate for informal settings like talking with family or friends.
If you just wish to state that you believe there is some alcohol in your blood, then the first sentence is OK. If you feel a little unsteady or dizzy, then the second sentence may be more applicable. The 'brethalyzer test' in the UK refers to the breath test administered by traffic police to drivers who are suspected of drinking and driving.
このシチュエーションのため、短くてよく使われる表現があります。こういう表現は "I'm still feeling it" です。これは日本語に翻訳すれば、「まだ、残っている」を表します。でも、この表現はお酒だけじゃなくて、ケガなど痛みがずっとがあれば、"I'm still feeling it" と言えます。
もっとはっきりと言ったかったら、"I'm still feeling the alcohol" も言えます。
When you talk about alcohol still being in your body from before then a common term is 'there's still some alcohol in my system' this is usually if you had a bit to drink the night before
there's still some alcohol in my system' は「酒（アルコール）がまだ体に残っている」の一般的な言い方です。これは普通、前の日の夜に少しお酒を飲んだ場合です。
There is still some alcohol in my system because I am a bit drowsy.
Alcohol still lingers on in my body because I still feel a little drunk.
Sometimes, alcohol does completely finish in person's system and can still affect him/her the following day. The effects may not be adverse, such as those of a hangover, but rather positive, such as feeling a bit drowsy or a little drunk. This type of feeling signals the fact that alcohol that was taken the previous day or night still lingers on in one's system. The adjective 'drowsy' used in the first statement means 'sleepy' in this context. The phrasal verb to 'linger on' means 'to be slow to disappear'. In this case, alcohol is slow to disappear from the system.
So, you may say:
There is still some alcohol in my system because I am a bit drowsy.
or
Alcohol still lingers on in my body because I still feel a little drunk.
お酒を飲むと、アルコールが体から完全には抜けず次の日まで残ることがあります。二日酔いほどはひどくないものの眠気や酔いを少し感じるときです。このような症状は、体にまだアルコールが残っていることを表します。
一つ目の例で使われている形容詞 'drowsy' はここでは「眠い」という意味です。
句動詞 'linger on' は「なかなか消えない」という意味です。この場合は、アルコールがなかなか消えないということ。
次のように言えます。
There is still some alcohol in my system because I am a bit drowsy.
（ちょっと眠いから、まだ体にアルコールが残っている）
Alcohol still lingers on in my body because I still feel a little drunk.
（まだ少し酔っている感じがするからアルコールが体に残っている）
I can still feel the effects of the alcohol in my system.
I am feeling nauseous from the alcohol in my system.
If you are trying to inform someone that you drank too much alcohol, then you can use the first sentence. This will be applicable to any conversation you might have with anybody.
When you are describing the feelings you have, dizzy, unsteady, drowsy, or have vision problems because you drank too much, then you can use the second sentence.
If you are feeling sick and have a headache, you can use the third sentence.
applicable - apply
drowsy - feeling sleepy
vision - sight / to see
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