わYou know?, Oh?, Ever so, Oh how I ever (emphasis)

The sentence-ending particle わ initially stems from the adverbial particle は, however, they are used in quite different ways. わ will primarily be used by women to either emphasize something, or for the purpose of convincing the person they are talking to that their statement is true.

This could be translated as 'you know!', 'oh?', 'ever so (A)', or 'oh how I ever (A)' in English, where (A) is some fact that they want to highlight.

わ may be used after the plain form of words, which means any verb, adjective, or auxiliary verb in their unconjugated forms.

Note that both だ and です are acceptable. This is because both だ and です are different auxiliary verbs that are in their plain form, rather than one being a conjugation of the other.

Usage of わ by younger women is becoming less and less common in recent generations.

Caution

わ may also be used by men. However, this use puts emphasis on either surprise or light exasperation. This exasperation is usually in relation to something that is true, but cannot be helped.

わ used by men for these purposes is still very common in some parts of Japan. Particularly the west. Thankfully, there is a very obvious pitch difference between the わ that is used in female speech, and the わ that is used in male speech.