Answer:
He wants to go to the concert, but he has a lot of homework tonight.
Step-by-step explanation:
To create a compound sentence out of your two simple sentences, you need to use a conjunction to join them. In this case, the most logical conjunction you can use would be "but." Therefore, your sentence would be:
He wants to go to the concert, but he has a lot of homework tonight.
To remember all of the conjunctions, you can use the acryonym FANBOYS.
This includes:
for, and, nor, but, or, yet, and so.