ごとに, どの〜も, 毎 differences


What is the difference between these three sentences, do they all mean "Every
city is big in America." ?

> アメリカはどの町も大きいです。

> アメリカは町ごとに大きいです。

> アメリカは毎町が大きいです。




Only the first sentence is natural.

The third one is probably understood but not idiomatic. [毎]{まい} is not such a
productive prefix. It's only used with counter words for things that happen
regularly such as 日, 週, 月, 年, and 回.

ごと (also written 毎) works more like _each_ than _every_. After 町ごとに I would
expect to hear something each town does on its own or some distinct
characteristic each town possesses. For example, the following sentence sounds
natural.

> アメリカは州ごとに法律が違う。

