The word "all" is a pronoun that refers to a large group of things or people, or it’s used to include 100% of a group.
All of the students passed the test. (100%)
All people need food, clothing, and shelter. (100%)
All of the houses in the neighborhood were destroyed by the storm. (100%)
We’re going to complete all of the work by tomorrow. (Notice that "all" is often–but not always–followed by the preposition "of.")
To show less than a hundred percent of something, put the word "not" in front of "all."
Not all of the passengers on the bus survived the crash.
Not all people have the same beliefs.
Not all of us are happy with the results of the election.
Use "all" in front of time expressions and times during the day:
The children slept well all night.
Rogelio and Alba spent all last week moving to their new house.
This project is going to last all year long.
The people behind us talked all during the movie.
What do you do all day?
Pay attention to the type of noun used with "all" in order to maintain subject-verb agreement:
All of the eggs are cracked. (eggs = count noun)
All of the rice is cooked. (rice = noncount noun)
All of his teeth are missing. (teeth = count noun)
All of the water is clean. (water = noncount noun)
Use "all" When trying to express how easy or simple something is.
All you have to do to start the car is push this button.
All they need in order to take the test is a pencil.
All she ever wanted was her mother’s respect.
Use "all" to express dissatisfaction:
Is this all of the pizza? Isn’t there more?
Is this all?
Is that all?
This can’t be all.
Are you sure this is all?
Where are all of my students today?
He used up all of the ketchup. There isn’t any more.
Many speakers of American English put the words "you" and "all" together to form a contraction: y’all. This is not grammatically correct, but it is a type of slang.
Y’all better listen up.
Y’all gotta come back soon.
What’s up, y’all?
(This is not how your teacher would ordinarily speak, but I thought it was important to include the examples above.)
