Expresses that two things happen together, or that as one thing changes, another changes with it. It has three uses: 'together with (a person/thing)', 'at the same time as / as well as', and 'as ~ (progresses), ~ (also changes)'. It is more formal than 一緒に.
[Noun / Verb (dictionary)] + とともに
家族とともに新しい町で暮らし始めた。
Kazoku to tomo ni atarashii machi de kurashi hajimeta.
I began living in a new town together with my family.
とともに means 'together with' the family (accompaniment).
年を取るとともに、体力が落ちてきた。
Toshi o toru to tomo ni, tairyoku ga ochite kita.
As I grow older, my stamina has declined.
とともに links two changes: aging and declining stamina occur in tandem.
彼はリーダーであるとともに、優れた研究者でもある。
Kare wa riidaa de aru to tomo ni, sugureta kenkyuusha demo aru.
He is a leader as well as an excellent researcher.
とともに means 'as well as', joining two simultaneous roles.
• With change verbs (増える, 変わる, 進む) it means 'as one thing changes, so does another'. • More formal/written than 一緒に; common in essays and news. • Noun + とともに can mean accompaniment ('together with') or addition ('as well as').
The JLPT rarely asks whether you recognise a pattern — it asks which of several similar patterns fits. These are the ones ~とともに is tested against.
と一緒に is casual 'together with', while とともに is formal and additionally covers 'as ~ changes' and 'as well as'.
につれて means 'as ~ gradually progresses (proportional change)' only, whereas とともに also covers accompaniment and simultaneity.
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