笨 (bèn): stupid, foolish

He learns things rather slowly, but he isn't stupid.

Don't call him stupid; he just hasn't found the right method.

This approach is too clumsy; let's switch to another one.

When I was little, I felt I was very stupid and couldn't learn anything.

He isn't stupid, just a bit lazy.

He is very slow-witted and learns things slowly.

This bear looks clumsy, but it's actually very agile.

You are really clumsy; you can't even hold a cup steadily.

This method is clumsy, but it is very effective.