Hello! This can be a delicate situation if one has a student who isn't very aware of the time. I like to warn my students a few minutes before time is up, so that things aren't too abrupt and they can ask questions if they have any. A couple examples that warn the student a little early would be:
"I'm afraid we're almost out of time for today, so I want to ask if you have any questions before we finish."
"Unfortunately, we've only got 2 minutes left for class today. Can you tell me in a few words how you felt about the material for today?"
もし生徒があまり時間を気にするようなタイプでない場合、ちょっと繊細な状況になりますね。
私の場合は、レッスン終了の数分前に一度もうすぐ終わることを伝えます。そうすることで、唐突な感じがせず、もし生徒が質問をしたい場合も余裕があります。
"I'm afraid we're almost out of time for today, so I want to ask if you have any questions before we finish."（残念ですがもうすぐお時間です。もしレッスンが終わる前に質問があれば教えてください。）
"Unfortunately, we've only got 2 minutes left for class today. Can you tell me in a few words how you felt about the material for today?（残念ですが、レッスンが終わるまであと２分になりました。今日のレッスン内容についてどう思われたか、短く言えますか？）
Our slotted time for our lesson/event is almost over, lets review what we discussed.
"It is time to wrap up our lesson/event." This idiom is very common and it is letting the student know that the time of the lesson is ending soon.
"Our slotted time for our lesson/event is almost over, lets review what we discussed."
Both of these sentences are a polite way of letting your student know that you are ending the lesson or the event.
"It is time to wrap up our lesson/event."（そろそろ時間ですね）
これはとてもよく使われるイディオムです。レッスンの時間が間もなく終わることを伝えています。
"Our slotted time for our lesson/event is almost over, let's review what we discussed."（もうそろそろ時間ですね。今日のおさらいをしましょう）
どちらもレッスンやイベントがもうすぐ終わることを知らせる時に使える丁寧な言い方です。
After 3 hours of interesting material...Let's wrap things up and be on our way...
When we use the idiom "wrap things up"...we infer its time to leave/close/ finish.
Its a common expression and can be shortend to: "OK that's a wrap!"
"After 3 hours of interesting material...Let's wrap things up and be on our way..."
"wrap things up"のイディオムを使う時、その場所を去る／会場を閉める／イベントを終了する時間を暗示します。
一般的な表現で、次のように短縮することができます。"OK that's a wrap!"（では、終わりにしましょう。）
"After 3 hours of interesting material...Let's wrap things up and be on our way..."（3時間の興味深い題材でしたが…終わりにして、帰りましょう。）
他の方がおっしゃっていない言い方をご紹介します。
お時間になりましたは
Let's call it a day.
とも言えます。
直訳すると「これを持って、今日と呼びましょう」ということで
「今日はここまでで終わりです」
と言いたい時に使います。
私も授業の時、いつも この、Ok, let's call it a day! 使っていますよ。
We can use all three of these interchangeably to mean the same thing. We can use, "reached," to mean that we've arrived at the end of our time. We can also either say that, "we're out of time," or that, "our time is up."
Well, our time has run out now. I've enjoyed today. Have a great evening!
Before abruptly stopping the lesson and using one of these expressions, you could also ask the student what they are going to do after the lesson, if they have any plans.
A"I'm going for a meal with some friends."
B "I'm sure you'll have a good time. Well, that just about wraps it up for today."
突然こういった言葉を投げかけてレッスンを終わらせるだけでなく、レッスンの後は何か予定があるのか聞いても良いでしょうね。
A"I'm going for a meal with some friends." ともだちと ご飯食べにいくんだ。
B "I'm sure you'll have a good time. Well, that just about wraps it up for today."きっと良い時間が過ごせるだろうね。じゃあ今日のまとめに入ろう。
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