'Unable' in the Bible

But when he did come out, he was unable to speak to them. They realized that he had seen a vision in the temple; and he kept making signs to them, and remained mute.

And there was a woman who for eighteen years had had an illness caused by a spirit (demon). She was bent double, and could not straighten up at all.

And they were unable to reply to this.

And another said, ‘I have [recently] married a wife, and for that reason I am unable to come.’

Otherwise, when he has laid a foundation and is unable to finish [the building], all who see it will begin to ridicule him,

for I will give you [skillful] words and wisdom which none of your opponents will be able to resist or refute.