'我一生中从未见过他'是一个否定句。

'I've never seen him in my life' is a ___negative sentence.

'Don't'和'do not'是'do'的否定形式。

'Don't' and 'do not' are ___negative forms of 'do'.

在语法中，否定陈述否认某事。

In grammar, a ___negative statement denies something.