particle N3 common casualpolitewritten

では — contrastive topic 'as for / when it comes to ~'

では

Meaning

in / at ~ (as opposed to elsewhere) — で (place/means/scope) marked with は for contrast

田舎いなかでは、こんな便利べんりな店みせは見みつからない。

In the countryside (unlike elsewhere), you won't find such a convenient shop.

Attaches to	Form	Example
Noun (で role-particle + は topic)	N + では	日本にほんでは / 口くちでは

日本にほんでは、車くるまは道路どうろの左側ひだりがわを走はしる。

In Japan, cars drive on the left side of the road.

口くちでは立派りっぱなことを言いうが、行動こうどうが伴ともなわない。

In words he says fine things, but his actions don't follow.

Sentence-initial では (casual じゃ) is a separate use — the transition 'well then / in that case': では、始はじめましょう.

Jengo shows では the way you actually meet it: inside real Japanese sentences, so it sticks instead of staying an abstract rule.

Sources Compiled with reference to A Dictionary of Advanced Japanese Grammar. Editorial confidence: medium.