What it means
てよかった expresses relief or satisfaction that an action happened. It is used when looking back on an action and saying that its result was good or fortunate. The action must be in the te-form, and the expression can be made polite by adding です.
Usage note
てよかった refers to a past or completed action, even though the verb appears in the te-form. Do not attach it directly to the dictionary form.
How to use it
Verb (て-form)よかったです
試験を受けてよかったです。
I’m glad I took the test.
Verb (て-form)よかった
試験を受けてよかった。
I’m glad I took the test.
Example sentences
雨が降ったので、洗濯物を中に入れてよかったです。
Since it rained, I’m glad I brought the laundry inside.
駅に着く前に切符を買ってよかったです。
I’m glad I bought the ticket before arriving at the station.
道に迷ったとき、交番で聞いてよかったです。
When I got lost, I’m glad I asked at the police box.