Mark can't afford a car unless he saves money every month.
Complex Sentence (Correct!)
Because the night sky is clear when it is so cold.
Complex Sentence (Incorrect -fragment)
The vacation was more expensive than we had planned, we decided to go anyway.
Compound Sentence (Incorrect - missing conjunction)
After every quarter, some students away to another city or state.
Simple Sentence (Incorrect - missing verb)
If Beth doesn't get new car tabs, she'll get a ticket.
Complex Sentence (Correct!)
Even though Emily skipped breakfast, but she still has a lot of energy.
Complex Sentence (Incorrect - delete "but")
Rosanne really wanted to learn to drive but she was too young to get a driver's license.
Compound Sentence (Incorrect - comma error)
At the same time, the baby’s cry also very pure.
Simple Sentence (Incorrect - missing verb)
Sean has a fear of heights he enjoys skydiving.
Compound Sentence (Incorrect - run-on)
I wasn't really hungry, but I ate lunch anyway.
Compound Sentence (Correct!)
Monica will pass the exam if she studies hard.
Complex Sentence (Correct!)
Since the storm was approaching.
Complex Sentence (Incorrect - fragment)
Even though I don't like to swim I love going to the beach in the summer.
Complex Sentence (Incorrect - comma error)
After picking up my daughter from school, I drove home, then I had lunch.
Compound Sentence (Incorrect - missing conjunction)
During the ESL graduation, is a special time to honor students' hard work.
Simple Sentence (Incorrect - missing subject)
In the middle of summer, the sky is often clear at night.
Simple Sentence (Correct!)