Please make sure to turn off all of the lights before going to bed.
To conserve energy, please turn off the lights before bedtime.
Turn off the lights before you go to sleep.
I used three different methods of saying the same thing.
In America, we say "go to sleep" which is interchangeable with "go to bed".
If you want to be very informal, you may use "hit the lights" or "hit the switch".
That means, turn off the lights.
Informal expressions for "going to bed":
"Turning In"
EX: Hit the lights before turning in.
"Hitting the hay"
EX: Before you hit the hay, hit the switch.
"Hitting the sack"
EX: Turn off the lights before you hit the sack.
"Retiring for the night"
EX: If you are retiring for the night, be sure to hit the lights.
I used three different methods of saying the same thing. In America, we say "go to sleep" which is interchangeable with "go to bed".
同じことを表す三つの言い方を紹介しました。
アメリカでは、go to sleep（go to bedと一緒）をよく使います。
カジュアルに言いたければ、hit the lights, hit the switch tuen off the lightsなどを使いますね。
「寝る」のカジュアルな言い方。
"Turning In"
例
Hit the lights before turning in.
寝る前に電気消してね
"Hitting the hay"
例
Before you hit the hay, hit the switch.
寝る前に電気消してね
"Hitting the sack"
例
Turn off the lights before you hit the sack.
寝る前に電気消してね
"Retiring for the night"
例
If you are retiring for the night, be sure to hit the lights.
お休みになるのなら、ちゃんと電気消してね。
Please make sure the light does not stay on all night
Sometimes people like to read books or watch TV in bed, or surf the internet on their phone or tablet. It is easy for them to nod off and leave the light on all night. You can ask them to 'make sure' the light is turned off.
make sure = ensure that something is done or happens.
"He wanted to made sure that his sons were well educated"
check, confirm, make certain.
To nod off = fall asleep, especially briefly or unintentionally.
"He nodded off during the sermon"
ベッドで横になりながら携帯でネットをしたり、テレビをみたり本を読むのが好きな人もいますよね、それでそのまま電気をつけたまま寝てしまう人もいるのではないでしょうか？相手に電気をちゃんと消すようmake sureすることができます。
make sure = ちゃんとそうするように確認すること
例："He wanted to made sure that his sons were well educated"
To nod off =眠ってしまう
例："He nodded off during the sermon"
The electricity bill was huge this month...Don't fall asleep with the lights on!
A clear and simple message is always best in order to get the message across!
Going to bed does not neccessarily mean sleeping:-) we should be more specific...
"The electricity bill was huge this month...Don't fall asleep with the lights on!"
メッセージを伝えるには明確でシンプルなメッセージが良いです。
Going to bedは必ずしも眠ることを意味しているとは限りません。もっとはっきりした言い方が良いです。
例文：
"The electricity bill was huge this month...Don't fall asleep with the lights on!"
（今月の電気代が高いので、電気をつけたまま寝ないでください。）
can you switch the lights off before you go to sleep
examples
"don't forget to turn off the lights before you go to bed".
or
"don't forget to switch off the lights before bed".
or
"can you switch the lights off before you go to sleep".
【例】
"Don't forget to turn off the lights before you go to bed".
（寝る前に電気を消すのを忘れないでね）
"Don't forget to switch off the lights before bed".
（寝る前に電気を消すのを忘れないでね）
"Can you switch the lights off before you go to sleep".
（寝る前に電気を消してくれる？）
You can say :
Please turn off the light when you go to bed.
Please switch off the light when you go to bed.
Don't forget to turn off the light when you go to bed.
Do you mind switching off the light when you go to bed.
このようにいうことができます。
Please turn off the light when you go to bed.
寝る前に電気を消してね。
Please switch off the light when you go to bed.
寝る前に電気を消してね。
Don't forget to turn off the light when you go to bed.
寝る前に電気を消すのを忘れないでね。
Do you mind switching off the light when you go to bed.
寝る前に電気を消すこと注意してね。
We can either use the term, "before going to bed," or say, "before sleeping," to mean the same thing. We can either say, "to turn off," the lights or also, "to switch off," the lights as well.
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