A conjunctive expression used after the past tense of a verb to indicate that another event occurred immediately after (equivalent to 'no sooner than' / 'as soon as').
家に着いたと思うと、すぐに電話が鳴った。
No sooner had I arrived home than the phone rang.
彼が席を立ったと思うと、部屋が急に静かになった。
Just after he stood up, the room became suddenly quiet.
雨が止んだと思うと、また降り出した。
No sooner had the rain stopped than it started again.
Used to express a feeling or reaction when one thinks of something (meaning 'when I think about...' or 'at the thought of...').
彼女のことを思うと、今でも胸が締め付けられる。
When I think of her, my chest still tightens.
将来のことを思うと、不安で眠れなくなることがある。
When I think about the future, I sometimes feel so anxious I can't sleep.
あの時の失敗を思うと、今でも顔が赤くなる。
When I think about that failure, I still get embarrassed.