"We made a few careless mistakes, and they jumped right in."

Or, you may race through a project just to get it done and make a lot of careless mistakes.

When she learned of it through my careless mistake, that knowledge was devastating to her and to our marriage.

Yet she knew it was precisely the kind of careless mistake they could ill afford.

But that would be a careless mistake on her part.

"We made a couple of careless mistakes early and the defense kept us in the game," he said.

I just kept thinking, 'Why are we making so many careless mistakes?

They always cause problems such as almost being crashed into a car due to the boys' careless mistakes.

You are simply inviting him to make a careless mistake.

Her grades are quite good even with the careless mistakes that she would often make.