A. Examples of Indefinite Pronouns
all, both, every, everything, each, some, somebody, someone, something, any, anybody, anyone, anything, none, either, neither, one, other, another, nothing, most of

B. Both, Either, Neither
Both: Means "two (things / people)" and is often followed by of + plural noun or and.
Either: Means "one or the other of the two (things/peOple)" and is followed by of + plural noun or or.
Neither: Means "not either one of the two (things / people)" and is followed by of + plural noun or nor.

C. Some, Any
Some: Used in affirmative sentences.
- Some can be used in questions when an affirmative answer is expected.

Any: Used in questions or in negative sentences.

D. One, Another, . . .
One / The other: Used when there are two things / people, etc.
- Of the two pens, one is red and the other is white.
One / Another / The other: Used when there are three things/ people, etc.
- He has three brothers: one is a doctor, another is a professor, and the other is a singer.
One / Another / The others: Used when there are more than three things / people, etc.
- We have five dogs: one is from Scotland, another is from Germany, and the others are from Spain.

E. Most of vs. Most
Use most of to talk about particular things or people, and use most to talk about things or people in general.
- Most of the students in this class are freshmen.
- Most people love music.