I have been using Aedict on Android and I really like it.

I see — thanks for explaining. I think I somewhat get it now.

These are from a multiple choice test

靴を○○、家に入り下さい。

1）脱ぎ終えたら
2）脱いだとたん
3）脱ぎだしたら
4）脱いだとしたら

And I understood why 2) and 3) were wrong but not why 1) was right and 4) was not.

I do not know whether 入り下さい is wrong as opposed to 入って下さい but then it is a typo in the test. Could you explain why this probably is a typo in the original document?