筆箱の中にペンあったって英語でなんて言うの？

Sometimes, when you look somewhere for something but it is in an obvious location, we use the phrase "the whole time." I hope that this helps :)

At times, we may misplace a certain object such as a pen. If we end up finding that pen in our pencil case, there may be a few different expressions we can use such as: 1) It was in my pencil case! 2) I found it in my pencil case. 3) It was there all along in my pencil case!

Saying that something was somewhere "after all" or "all along" expresses that it was some place expected that you perhaps overlooked. It also expresses that you felt some stress or frustration at losing it or finding it in a predictable place, for example: "My door keys were in the door all along!" Saying that something was right under your nose should not be taken literally. This just means that an item or a fact was closer to you than you originally thought, for example, "The answer was right under my nose!"

Well, I'll be' is an idiomatic phrase meaning 'surprise or astonishment, especially regarding some recent discovery.' You can also just say 'I'll be.'

Either of the examples above would be a good way of telling someone that you found your pen in your pencil case.

When you couldn't find your pen - but then found it, (it had been in your pencil case).... you want to say that it was in your pencil case. Any of the above suggestions does just that.

We all know how frustrating it is when you can't find your pen! To explain that your pen was in your pencil case while you were searching for it, you can say that it was there 'all along' to show that you had been looking in other places when your pencil case should have been the first place to check. "I looked everywhere for my pen only to find it was in my pencil case all along, what a waste of my time!"