The correctly formed compound sentence is:
Daniel was very excited to watch his favorite team play, but they lost.
This sentence properly connects two independent clauses using the coordinating conjunction "but" and includes a comma before "but."
Daniel was very excited to watch his favorite team play. But they lost.
Daniel was very excited to watch his favorite team play but they lost.
Daniel was very excited to watch his favorite team play, but they lost.
Daniel was very excited to watch his favorite team play; but they lost.
1 answer
The correctly formed compound sentence is:
Daniel was very excited to watch his favorite team play, but they lost.
This sentence properly connects two independent clauses using the coordinating conjunction "but" and includes a comma before "but."