pretty

[Abstract Idea]

Is it correct to use 'pretty' as an adverb intensifying negative adjectives?
For example as in:
1) "She is pretty depressed."
2) "He was pretty bad in the test - he got an E."
3) "That was a pretty ugly witch."

Or is the adverb 'pretty' used only with positive qualities such as:
1) "She is pretty creative."
2) "He did pretty well in his test - he got an A."
3) "That was a pretty beautiful witch."?

PS Please correct any possible mistakes in this post.

[bhaisahab]

Is it correct to use 'pretty' as an adverb intensifying negative adjectives?
For example as in:
1) "She is pretty depressed."
2) "He was pretty bad in the test - he got an E."
3) "That was a pretty ugly witch."

Or is the adverb 'pretty' used only with positive qualities such as:
1) "She is pretty creative."
2) "He did pretty well in his test - he got an A."
3) "That was a pretty beautiful witch."?

PS Please correct any possible mistakes in this post.

Yes, you can use it to intensify negative adjectives. "Pretty" is one of those words which have changed meaning/useage it's origins are:
Online Etymology Dictionary

[konungursvia]

I was almost expecting Bhaisahab to point out it's not as common in BrE as in AmE, but I suppose it's once again getting quite common there too.

[bhaisahab]

I was almost expecting Bhaisahab to point out it's not as common in BrE as in AmE, but I suppose it's once again getting quite common there too.

Yes, it's pretty common in BrE too.