My daughter's in sixth grade and has a fantastic concept of proper grammar. Sadly or funny enough, I find myself asking her when I am stuck on punctuation...So, cue FANBOYS:
Connector clause 1 clause 2 complex sentence
FOR He couldn't go home. He had no place to go. He couldn't go home, for he
reason had no place to go.
AND I took a taxi. She drove home. I took a taxi, and she drove
NOR He didn't want help. He didn't ask for it He didn't want help, nor did
not he ask for it.
BUT I wanted to go late. She wanted to go on I wanted to go late, but she
contrast time. wanted to go on time.
OR She cooked dinner. He took her out to a She cooked dinner, or he took
options restaurant. her out to a restaurant.
YET She owned a car. She didn't know how to She owned a car, yet she outcome drive it. didn't know how to drive it.
SO She had to go. She called a friend to She had to go, so she
result drive her. called a friend to drive her.