「[光陰矢の如し（時間が早く過ぎる）](https://eikaiwa.dmm.com/uknow/questions/55060/)」ということわざで
Time flies.
というものがありますので、それを過去形で
Time flew.
Time just flew.
Time flew so fast.
など言えば、時間が[あっという間](https://eikaiwa.dmm.com/uknow/questions/28690/)に過ぎ去った感じが出ます。
Time flies when you're having fun（楽しい時間はあっという間に）という定番の英語フレーズもあります。
また「過ぎる」ことは pass を使うと表現しやすいです。
I can't believe that two hours passed.
２時間が過ぎたなんて信じられない。
などと付け加えるとなお良いのではないでしょうか？
If you use the expression "in the blink of an eye" you would not use a time frame to explain how much time passed by in the same sentence. This idiom means that time passed by extremely quickly. The time passed could be an hour, five hours, or a day, depending on your experience. If you need to explain that 2 hours passed by, you can add that in another sentence.
e.g. It felt like we were home in the blink of an eye! It took us 2 hours, but it felt so fast!
You can also say that "time escaped you" as in, you didn't notice or realize how much time had gone by, you lost track of time. Often people would say this when they are deeply focused or immersed in some type of activity they are highly interested in.
e.g. We should leave for dinner now, 2 hours have passed! I'm sorry, the time escaped me.
"in the blink of an eye" を使う場合、同じ文の中に時間を表す言葉は入れません。"in the blink of an eye" は、時間がすごく早く過ぎたことを表します。その「時間」は1時間かもしれませんし、5時間、1日かもしれません。あなたの経験によります。
「2時間」と伝えたいなら、別の文で言います。
例：It felt like we were home in the blink of an eye! It took us 2 hours, but it felt so fast!
（あっという間に家に着いたね。2時間かかったんだけど、すごく早く感じた）
また、時間がたつのを忘れた時などは、"time escaped me" と言うことができます。何かにすごく集中したり、没頭した時によく使われます。
例：We should leave for dinner now, 2 hours have passed! I'm sorry, the time escaped me.（もう夕御飯だから帰りましょう、2時間もたってる。ごめんなさい、時間忘れてしまって）
1. Flashed by = passed really quickly. "The racing car flashed by us."
2. This is a a well known idiom. It means that time passes quickly when you are enjoying yourself.
3. This question is asked for dramatic effect.
1.Flashed by =本当にすぐに通り過ぎて行った。 "The racing car flashed by us."：「レーシングカーが私たちの前をすごいスピードで通り過ぎて行った」
2. これはよく知られているイディオムです。楽しんでいるとき時間がすばやく過ぎるという意味です。
3.この質問はよりドラマティックに時の流れの速さを表現する言い方です。
Time flies when you are having fun. Two hours just flew past me.
I can't believe that two hours went by so quickly. Time sure flies.
The idiom 'time flies' is said when time has passed by so quickly that you did not notice it. You might have joined the party two hours ago, but, because you have been having so much fun, the two hour just flew past you so quickly that you can not believe it.
So, you may say:
Time flies when you are having fun. Two hours just flew past me.
or
I can't believe that two hours passed by so quickly. Time sure flies.
time flies'というイディオムは、あなたが気づかないほど時間がとても早く経ったというときに使われます。2時間前にパーティに参加したかもしれませんが、あまりにも楽しんでいたので、とても早く2時間が過ぎて、信じられないというときもあるでしょうね。
以下のように言うといいでしょう。
Time flies when you are having fun. Two hours just flew past me.
（楽しんでいるときは、時間が経つのが早いです。2時間あっという間でした。）
I can't believe that two hours passed by so quickly. Time sure flies.
（2時間がこんなに早く過ぎるなんて信じられません。時間は本当にあっという間に過ぎますね。）
Wow, look at the time! Those 2 hours just flew right by!
Boy, time sure does go by quickly! 2 hours have already passed!
Wow, would you look at the time? Those 2 hours just flew right by me!
Wow, look at the time! - this is bringing the listener's attention to the time/hour
Those 2 hours just flew right by! - to fly by implies to move quickly because things that fly often move quickly... so quickly that they are gone before you even notice
Wow, would you look at the time? - this is a rhetorical question, so you don't need to actually look at the time. It is just calling attention to the time.
Boy! - this is one way to express, "oh wow" and surprise/emphasis
例文
Wow, look at the time!
わぁ、時間を見て！！
聞いている人の注意を時刻/時間に向けさせています。
例文
Those 2 hours just flew right by!
2時間が本当にあっという間に経った。
- to fly byは飛んでいるものはとても速く飛ぶので、とても速く動くと
いうことです。とても速く飛ぶので、気づいたらいなくなっています。
Wow, would you look at the time?
わぁ、時間を見て！！
この文は修辞疑問文ですので、実際に時間を見る必要はありません。
ただ時間に注意を向けさせています。
Boy!
まぁ。
"oh wow" を表す1つの表現方法で、驚きと強調を表しています。
time flies = time went by quickly (it has nothing to do with being in the air or off the ground)
I can't believe = it's shocking or it's a surprise
Usually if your enjoying yourself time seems to go very quickly but on the other hand if it's something you don't like doing time seems to go very slowly.
Therefore if 2 hours passed by quickly chances are you were enjoying yourself
time flies = 時間が早く過ぎた（空中を飛ぶこととは関係ありません）
I can't believe = ショックまたは驚きである
通常、楽しんでいると時間が過ぎるのは早く、好きではないことをしていると時間が過ぎるのがとても遅く感じられます。
よって、2時間がとても早く過ぎたのであれば、あなたは楽しんでいたと言えるでしょう。
Time's flying by today - This means that the hours today are going so fast.
Where did them two hours go - Saying this means the last two hours have gone so fast.
Time's flying by today
=「今日は時間が過ぎるのが早い」という意味です。
Where did the two hours go（この2時間はどこに行っちゃたの）
= 「この2時間があっという間だった」という意味です。
こんにちは。
様々な言い方ができると思いますが、例えば以下のような英語表現はいかがでしょうか：
Two hours flew by.
あっという間に2時間がたちました。
Has it really been two hours already?
本当にもう2時間たったんですか？
ぜひ参考にしてください。
Here we can use the expression that the time, "flew by," or, "flashed by," without us really realizing or having it feel like it was really that long.
We can also say that we, "lost track of the time," to express that same idea.
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