I slept through most of the outward and the return trip.
Explanation: To sleep through something means to be asleep while something is happening. You may say, '..right through' to mean 'completely through without break.'
Example sentence:
"As I had been drinking the night before, I slept right through the earthquake!"
To sleep through something とは、何かの間寝ているという意味です。 '..right through' は、休憩なくずっとという意味です。
例文：
"As I had been drinking the night before, I slept right through the earthquake!"
昨夜お酒をずっと飲んでいたので、地震の間も寝ていた。
I was asleep for most of the journey there and on the way back
I slept for most of the journey both ways
If you want to say that you were sleeping in the car then you could say 'I was sleeping' or 'i slept'
Most of means not all but alot of the time
A journey is a trip you take in a vehicle. As well as saying there and on the way back you can also say both ways they both mean the same thing
車の中で寝ていたことは、
'I was sleeping'（寝ていた）
又は、
'I slept（寝た）'
と表せます。
'most of'は「多くの時間」という意味です。
'journey'は乗り物に乗ってある所から別の所まで移動することを表します。
"there and on the way back"（行きも帰りも）は"both ways"（行きも帰りも）と言うこともできます。どちらも同じ意味です。
We went to my in-laws house, by car...I slept for most of the journey, there and backl!
Long journeys in the car send many of us (not driving;-) to sleep ;-D
In this case we need a simple all-encompassing phrase" to fit the bill"
"We went to my in-laws house by car,I slept for most of the journey, there and backl"
車での長旅は私たちを眠りを誘いますよね;-)
(運転中はだめですよ） ;-D
この場合、シンプルにあらゆるものを含んだ表現が必要です。
"to fit the bill"（目的にぴったり合う）
【例文】
"We went to my in-laws house by car,I slept for most of the journey, there and back"
（夫の実家へ車で行きましたが、行き帰りの車の中ほとんど寝ていました）
I was asleep for a majority of our trip, both back and forth.
I wasn't awake for the drive to and from my in-law's house.
The two sentences you see provided above are excellent ways to express to your listener that you were asleep while driving to your destination and from your destination. In the first sentence you will see the term back and forth. We use this to describe going to a location and returning from a location. This is a term that is common in our everyday conversation and it would make a great addition to your vocabulary.
どちらも、目的地への行き帰りの間車の中で寝ていたと伝える言い方です。
最初の例文では、"back and forth"という表現に気が付いたと思います。これは、どこかに行って帰ってくることを表します。日常会話でよく使われる表現なので、語彙に加えておくといいでしょう。
If alreaady engaged in a conversation about your sleeping on the drive, i slept the whole way would provide enough information.
If you wanted to ensure your tiredness was understood, specifing the return journey would add emphasis.
移動中に車の中で寝てしまったことについて、既に会話をしている最中であれば、”I slept the whole way"（道中ずっと寝ていた）と言えば十分に伝わります。
寝てしまった理由でもある「疲労感」を相手にわかって欲しい場合、帰り道について触れることで強調することが出来ます。
I was asleep for most of the way there as well as the way back
I was asleep on the drive to and from my in-laws house
When you want to explain that you were asleep for most of the way to your in-laws and also on the way back; then you may explain it in the following ways:
-I was asleep for most of the way there as well as the way back
-I was asleep on the drive to and from my in-laws house
ご主人の実家に帰省した時、行きも帰りも移動中ほとんど寝ていたのなら、以下のように表せます：
【例文】
-I was asleep for most of the way there as well as the way back
［訳］行きも帰りもほとんど寝ていました
-I was asleep on the drive to and from my in-laws house
［訳］夫の実家に帰省した時は、行きも帰りも車の中で寝ていました
I slept in the car on the way there and the way back.
こんにちは。
様々な言い方ができると思いますが、例えば下記のような表現はいかがでしょうか：
・I slept in the car on the way there and the way back.
行きも帰りも車の中で寝ていました。
the way there - 行き
the way back - 帰り
ぜひ参考にしてください。
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