Translation guide
Expressing that two or more events occur simultaneously, or referring to a specific point in time that is shared.
The learner wants to say that two actions or events happen concurrently.
Attach to the ます-stem of a verb to mean 'while doing'. The subject must be the same for both actions.
音楽を聴きながら勉強した。
I studied while listening to music.
Used after dictionary form of verbs or nouns to mean 'at the same time as'. Can be used when subjects differ.
彼が入ってくると同時に電話が鳴った。
The phone rang at the same time as he came in.
Literally 'together with', but can imply simultaneous occurrence when used with events.
地震と一緒に停電が起きた。
A power outage occurred at the same time as the earthquake.
Adverb meaning 'simultaneously'. Can be used at the beginning of a sentence.
二人は同時に話し始めた。
The two started speaking at the same time.
The learner wants to refer to a particular moment that is identical for two or more things.
Direct translation meaning 'the same time/hour'. Used for scheduled times.
毎日同じ時間に起きる。
I wake up at the same time every day.
More formal/literary than 同じ時間, meaning 'the same hour/time'.
会議は毎週同時刻に開かれる。
The meeting is held at the same time every week.
The learner wants to introduce a contrasting or additional point, similar to 'at the same time' as a discourse marker.
Means 'on the other hand' or 'at the same time' when presenting a contrasting idea.
彼は優しい。その一方で、厳しいところもある。
He is kind. At the same time, he can be strict.
Can also be used as a conjunction meaning 'at the same time' in a contrasting sense, though less common than その一方で.
この計画は魅力的だ。しかし同時にリスクも大きい。
This plan is attractive. At the same time, however, the risks are great.