It started well and turned out terribly.

[wotcha]

'It started well and turned out terribly.'

Is this sentence grammatically correct?

 

[5jj]

Yes

 

[Tdol]

It is, but you could also use but there.

 

[AKB48]

It started well and turned out terribly.
Would it be okay to say "terrible" in place of terribly?

 

[riquecohen]

I think that would be a terrible idea. Use the adverb, terribly.

 

[AKB48]

Thank you for the response, riquecohen. Is it wrong to place an adjective after "turn out"?

The craft — a hollowed-out construction paper heart pressed between two pieces of contact paper in which colorful tissue paper had been arranged — turned out great. (Late-night baby steps led to Pinterest 
interest | GoErie.com/Erie Times-News)

Should great be "greatly"?

 

[Tdol]

Not always- in your example, the adjective is correct as it is describing the craft.

 

[AKB48]

Thank you for the response, Tdol. I still don't understand why "turn out terribly" and "turn out great" are correct, or why "turn out terrible" and "turn out greatly" are incorrect or not always correct.