Daniel defoe........... is founder of english novels
Ok sure do you want me to type it here?
This is punctuated correctly.
"Marshmallows are my favorite snack" is a complete sentence unto itself.
The comma instead of a period shows that the sentence spoken is part of the whole sentence, which includes the speaker (she) and a word to describe how the speaker said it (explained).
You will have to earn the credits lost in the first semester like retake anything from last semester and its not really relevant that you get a higher grade the next semester you going to have to retake the last semester in one way or another