I made a mistake about the time.
時間を間違えた。
I had the wrong time in mind.
違う時間を考えていた。
こういう意味ではあまり「mistook」（"I mistook the time"）とは言いません。「mistook」は、人か物を見たら正体を[間違えた](https://eikaiwa.dmm.com/uknow/questions/38154/)ときに使います。
I didn't know this guy, but I mistook him for my friend.
知らない人だったのに、友達に[人違い](https://eikaiwa.dmm.com/uknow/questions/32766/)した。
"I made a mistake with our class time."
"I got confused about the time of our class."
Teacher: Hi, good evening! Welcome back to our class. :)
Student: Hi, teacher. I'm sorry I wasn't able to answer your call the last time. I got confused about our schedule. I'm sorry again.
or
Student: Hi, teacher. I'm very sorry for not attending our class last time. I made a mistake with our schedule. It won't happen again.
Using the word 'confused' or 'made a mistake' mean the same thing in this case. Feel free to use either of them. Both are easily understood.
"I made a mistake with our class time."(私は授業の時間を[間違えてしまいました](https://eikaiwa.dmm.com/uknow/questions/38154/))
"I got confused about the time of our class."(授業の時間について[混乱してしまいました](https://eikaiwa.dmm.com/uknow/questions/55139/))
先生: Hi, good evening! Welcome back to our class.(こんばんは！授業へまたようこそ。)
生徒: Hi, teacher. I'm sorry I wasn't able to answer your call the last time. I got confused about our schedule. I'm sorry again.(先生こんにちは。前回通話に出ることができず申し訳ございません。スケジュールを混乱してしまいました。再度お詫びいたします。)
または
生徒: Hi, teacher. I'm very sorry for not attending our class last time. I made a mistake with our schedule. It won't happen again.
(先生こんにちは。前回の授業を受けずすみません。予定に関して間違えを犯してしまいました。次からはこのようなことは起こりません。)
'Confused'(混乱した)と'made a mistake'(間違えを犯した)の使用はこの場合は同じ意味です。どちらもご気軽にお使いください。どちらも簡単に理解可能です。
To slip one's mind = Be overlooked or forgotten, as in:
" I meant to pick up the wine but it slipped my mind."
Or, you may have mistaken the start time of the lesson:
"I thought the lesson was starting later!"
To have a senior moment = a temporary mental lapse (humorously attributed to the gradual loss of one's mental faculties as one grows older). However, you do not have to be old to have a senior moment!
"Adults understand the idea of saving electricity, but are subject to occasional senior moments of forgetfulness."
To slip one's mind = 忘れる、見落とされる
" I meant to pick up the wine but it slipped my mind."
（ワインを買うつもりだったけど、すっかり忘れてしまった）
または、レッスンの開始時間を勘違いしてしまったかもしれません：
"I thought the lesson was starting later!"
（レッスンはもっと後に始まると思っていました）
To have a senior moment = 一瞬物忘れをしてしまう事、年寄りの物忘れ
(人間の特徴として年を取っていくにつれて物忘れをするようになるものです）
しかし、年寄りの物忘れは年寄りだけがするものではありません！
"Adults understand the idea of saving electricity, but are subject to occasional senior moments of forgetfulness."
（大人には節電の考えはありますが、しばしば年寄りの物忘れをしてしまいます）
When you got the time incorrect or mistaken the time you can use the following expressions listed above.
I am sorry is always a good way to start and then explaining why you got the time wrong.
I am so sorry I got the time wrong
I made a mistake with the time
I got the time wrong
時間を間違えた場合は上記の表現を使用することができます。
"I am sorry"(申しわけございません)から始めることはなぜ時間を間違えたのかを説明する際に良い方法です。
I am so sorry I got the time wrong (時間を間違えて本当に申しわけございません)
I made a mistake with the time(時間に関する間違えを犯しました)
I got the time wrong(時間を間違えました)
I am sorry for being late but I mistook the lesson start time.
I am sorry for being late but I thought my lesson was starting a bit later.
Please excuse my tardiness. I thought my class start time was a bit later.
If you did not answer the call because you had mistaken the class time you may simply say the following to your teacher;
I am sorry for being late but I mistook the lesson start time.
mistook- past tense of mistake
I am sorry for being late but I thought my lesson was starting a bit later.
Please excuse my tardiness. I thought my class start time was a bit later.
tardiness- The quality or fact of being late; lateness.
It is polite to always apologize when one is late.
授業時間を間違えてコールに出れなかったとき、先生には下記の通り言えます。
I am sorry for being late but I mistook the lesson start time.
遅れてすみませんが、授業開始時間を間違えました。
mistook- mistake（間違える）の過去形
I am sorry for being late but I thought my lesson was starting a bit later.
遅れてすみませんが、授業がもう少し遅く始まると思ってました。
Please excuse my tardiness. I thought my class start time was a bit later.
私が遅刻したことを許してください。授業がもう少し遅く始まると思ってました。
tardiness- 遅刻、遅延
遅れた時は、いつでも謝ることが礼儀正しいです。
I misread the schedule. I thought class was at a different time.
My bad! I didn't realize that class was at that time,
These are phrases to express that you were mistaken about the time of the class. It's an honest mistake but it's important to apologize. These things happen when you don't pay attention.
I confused my lesson start time and I missed your 1st call.
I missed your previous call because I thought my lesson was only later today.
▪I confused my lesson start time and I missed your 1st call.
confused=
This indicates that you got your lesson start time mixed up and missed the previous call.
▪I missed your previous call because I thought my lesson was only later today.
This explains that the reason you missed the call because you had a different start time in mind.
Example 1
Teacher: Hi, you missed my 1st call. Where were you?
You: I confused my lesson start time and I missed your 1st call.
Example 2
Teacher: Hi, you missed my 1st call. Where were you?
You:I missed your previous call because I thought my lesson was only later today.
▪I confused my lesson start time and I missed your 1st call.
(私はレッスン時間を混乱してしまったためあなたからの最初のコールにでられませんでした)
confused(混乱した)=
これはレッスン時間を混乱してしまい前回の電話をとり損なったことを示します。
▪I missed your previous call because I thought my lesson was only later today.
(レッスン開始時間がもっと遅いと思っていたのであなたからのコールにでられませんでした)
これは電話をとりそこなった理由が異なるレッスン開始時間を考えていたからであるということを説明しています。
例1
先生: Hi, you missed my 1st call. Where were you?
(こんにちは、あなたは私の最初のコールに応答しませんでした。どこにいたのですか？)
あなた: I confused my lesson start time and I missed your 1st call.
(私はレッスン時間を混乱してしまったためあなたからの最初のコールにでられませんでした)
例2
先生: Hi, you missed my 1st call. Where were you?
(こんにちは、あなたは私の最初のコールに応答しませんでした。どこにいたのですか？)
あなた:I missed your previous call because I thought my lesson was only later today.
(レッスン開始時間がもっと遅いと思っていたのであなたからのコールにでられませんでした)
おっしゃられている内容では、私ならよく以下のように言います(*^_^*)
I was mistaken about the time.
「時間を間違えていた、勘違いしていた」
なんらかの記憶違いや認識違いをしていた時に使える表現です。
I was mistaken about the place.
「場所を勘違いしていた」
なども言えます♪
以上です。
少しでも参考になれば幸いです(*^_^*)
★★大阪カフェレッスン英会話講師 KOGACHI
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