in case + 文章 《万が一》
Bring an umbrella in case it rains.
Save your work frequently in case the computer crashes.
コンピュータがクラッシュした場合に備えて、頻繁に作業を保存して下さい。
in case of .... [起こる可能性がある・予防措置]
In case of rain, bring an umbrella.
I will send you the seat number in case of my late arrival.
in the case of .... 【theで具体的に想定→可能性がある】
In the case of heavy rain, the event will be postponed.
In the case of emergency, please call this number.
In the case of disagreement, we will need to seek a mediator.
When ... 【予想される仮定→可能性がある】
Let’s have lunch when we meet next time.
Please give him my regards when you see him next time.
I will give a speech when our next team meeting takes place.
if ...(現在形) [可能性がある]
If the weather is good tomorrow, let's go hiking.
If you like, please take my seat.
If all goes well, we should arrive at our destination by sundown.
If you need my help, please don't hesitate to call me at any time.
if ...(過去形) [可能性が無い・非現実的] もし~だったら
If I had a car, I would drive to the coast every weekend to watch the sunset.
if I were ...
If I were you, I'd take the opportunity to travel while you have a chance.
If she were here, she would have brightened the room with her laughter.
もし彼女がここにいたら、笑い声で部屋を明るくしたことだろう