opens / opens up


I was wondering if there’s a difference between opens and opens up, for example:

He opens his eyes.

He opens up his eyes.

Thank you!

No. “Up” is often useless, as it is here.

When “open up” is idiomatic, there is a difference.

The singer opened up about his rumored affairs. - To address candidly

Sometimes it seems the difference is just one of formality.

“Clean” sounds a bit more formal to me than “clean up,” for instance. The latter is different from the former in a metaphorical sense, though. We rarely clean messes unless we mean it literally.