Can anyone tell me if I have done this right.
Because the store was closed.
my answer: Because the store was closed, we went back home without the food.
I think you did it correctly. I am not sure what the teacher was asking for.
But you took an incomplete sentence and made it make sense.
Yes, Matt's right. You took a sentence fragment (incomplete; subordinate/dependent clause) and made it into a complete sentence by adding an independent clause.
well I am trying to see if I use the correct Punctuating Sentences
The punctuation is also correct - GOOD JOB>