I'm often confused about when to use "all of" and "all". Is there any difference between the two?
Native speaker’s answer
Rebecca
"All" and "all of" mean the same thing, i.e. we use it to indicate how much of something we're discussing. For example, "all students" means "every single student," not just some of them. But you have to choose the right one depending on the following factors. Use "all of" when the next word is a personal or relative pronoun (me, you, us, them, whom, which).\ Ex: All of you were late to class. Ex: These are my students, all of whom were late. You can use either "all" or "all of" when the next word in the sentence is a noun phrase that begins with a determiner (the, this, that, these, those, my, his, her, your, our, their). Ex: All of the students overslept. => All the students overslept. Ex: The students lost all of their homework. => The students lost all their homework. Use "all" by itself when the next word in the sentence is a plural noun that refers to an entire class of things or an uncountable noun. Ex: All water is wet. Ex: All cats are lazy.
