What form of language shown in the following sentence The kid you babysat tonight certainly was a handful?

The sentence "The kid you babysat tonight certainly was a handful" uses idiomatic language.

Here's why:

* "A handful" is an idiom meaning "difficult to manage or control". It's not a literal description of the child holding a handful of something.

Idioms are phrases that have a figurative meaning that is different from the literal meaning of the individual words. They add color and expressiveness to language.