Is it a Fragment?
The grass was tall and.
Fragment. It has a subject and verb but does not convey a complete thought.
I like pizza I eat it every Friday.
Run-on. Two complete sentences pushed together
The student was happy.
Complete sentence.
It has a subject, predicate, and makes sense.
The big brown dog was barking.
Complete sentence.
The bell rang we hurried back to class.
Run-on. Two complete thoughts with no punctuation/conjunction.
Maria finished her homework before dinner she was ready to eat.
No, this is a run-on. There are two sentences pushed together with no connecting words.
The students sitting quietly at their desks.
Fragment. Has a subject, but the word "sitting" does not complete the thought.
Marcus finished his homework and decided to play a game.
Not a run-on. There is a subject and a compound predicate (2 predicates) connected by a conjunction "and".
After the rain stopped, the children hurried outside to play.
Complete sentence.
The beginning part before the comma tells when the rest of the sentence occurred. This is a complete, complex sentence.
When the teacher finally announced the winner.
Fragment. The word "when" at the beginning of the sentence leaves you waiting for what happened.
After we finished eating dinner, my sister washed the dishes, and I cleaned the table.
Not a run-on. This is a complete, complex sentence. The first part tells when the rest of the sentence happened and the two complete sentences are joined by ",and" (FANBOYS).
I need to do my homework, eat dinner, take a shower, study my notes, and then go to bed.
Complete Sentence.
Even though it looks like a lot of information, the sentence is listing things which need to be separated by a comma. It has a subject, predicated, and is a complete thought.
Although Maya had practiced her speech every night for two weeks.
Fragment. It has a subject and predicate but the word "although" leaves you wondering what happened next. Incomplete thought.
Although the storm had ended, the streets were still covered with water several families decided to wait before driving home.
Run-on! The beginning is correct, but “the streets were still covered with water” and “several families decided…” are two complete thoughts incorrectly joined.
When the final bell rang, the students packed their backpacks, pushed in their chairs, and hurried toward the door, but Mrs. Garcia reminded them that they needed to turn in their permission slips before they left.
Complete sentence!
Even though the sentence is extremely long, it has everything it needs to be complete. It is long because it is a complex sentence and a compound sentence in one.