'It started well and turned out terribly.'
Is this sentence grammatically correct?
It is, but you could also use but there.
It started well and turned out terribly.
Would it be okay to say "terrible" in place of terribly?
I think that would be a terrible idea. Use the adverb, terribly.
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"?
Not always- in your example, the adjective is correct as it is describing the craft.
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.