Sentence examples for it would certainly brighten from inspiring English sources

It would certainly brighten up brand Kate.

A win on Friday — or, improbably, Tuesday at the Azteca — would certainly brighten the team's mood and its chances.

It would certainly seem so.

It would certainly help.

And it would certainly be controversial.

It would certainly reduce shipping costs.

It would certainly appease any disgruntled supporters.

In most circumstances, it would, certainly.

It would certainly have lots of company.

Sure, it would certainly change things.

It would certainly be difficult.