我们应该质疑这些陈述的有效性。

We should question the ___validity of these statements.

这个陈述如此明显，我们几乎从不质疑其有效性。

This statement is so obvious we almost never question its ___validity.

他的论点的有效性是值得怀疑的。

The ___validity of his argument is doubtful.