2 Answers

You need a tutoring site. We are not that. We answer general questions, but don't do too much by way of homework or school work as we are not teachers and can not really work one on one with you as we have a lot of questions here and not enough help. My suggestion is to open your book and read. You should have been taking notes in class too, if you did, read them also. I grew up without a computer and managed to learn by reading my text books. I think you can learn without a computer too. 

Where were you when instruction was being provided????  I can give you a couple of hints. 
Sentence fragments:  Who or what is doing what?     If you can't answer that question without saying "I don't know", it's a fragment.       Running through the meadow.  Who is running through the meadow????   I don't know...FRAGMENT.        
Colons are generally used right before listing stuff. For example: bread, milk, orange juice, eggs.
Semi-colons are used to combine separate but connected thoughts:  I knew he was going to be late; waiting seemed like the polite thing to do.  (Those COULD have been separate sentences, but they are so related, I used a semi-colon to show a connected thought.)
"I'm not sure, " said Bob, "if you are going to understand the next part."  
In the beginning, a prepositional phrase might be separated from the rest of the sentence by a comma.  If you can take the phrase and put it logically elsewhere in the sentence, separate it with a comma.  Through the trees, Tom could see the cottage.  Tom could see the cottage through the trees.
OK, that's all I've got.  Good luck, and pay attention next time.