Don't be such a nitwit; double-check the address before you leave.

The nitwits tried to fix the leaky pipe with tape, so the bathroom flooded by evening.

Even though he tried to apologize, his nitwitted comment only made things worse.

Her nitwittedness during the debate cost the team their best chance at winning.

Her constant nitwittery at meetings frustrated the whole team.

He nitwittedly tried to fix the old clock with a hammer, only to make the problem much worse.

Even though his plans were well-intentioned, his nitwittish mistakes turned the celebration into a comic disaster.