We use SOMETHING for things
SOMEBODY or SOMEONE for people
SOMEWHERE for places.

We can also make compounds with ANY- and NO-:

ANYTHING, ANYBODY, ANYONE, ANYWHERE
NOTHING  /nʌθɪŋ/ NOBODY /nəʊbɒdɪ/ NO ONE /nəʊ wʌn/ NOWHERE /nəʊweə*/

The same rules that apply for SOME and ANY also apply for somebody/anybody, etc:
(you can read the rules on this other lesson: Some, Any, No)

He never does anything bad.
I need somewhere to sleep.
I know someone who could help us.
Do you know anyone who could help us?
I haven't got anything to eat = I've got nothing to eat

 
The plural of SOMEBODY or SOMEONE is "some people", the plural of SOMETHING is "some things", the plural of SOMEWHERE is "some places".

- There's somebody at the door
- There are some people waiting outside
- Look, I've got something for you, open it!
- I wanted to buy some things but now I can't remember what
- He lives somewhere near here
- You can find palm trees in some places near here

You never use a preposition before compounds with -WHERE

- She must be hiding in the mountains She must be hiding somewhere
- I'm not going to your house I'm not going anywhere / I'm going nowhere
- Are you going to the bar? Are you going anywhere?
 
You can also make compounds with EVERY-

- Everything = all the things
- Everybody/everyone = all the people
- Everywhere = in/at/to/on all the places

Notice that the verb is always singular
 
- Everything was quiet = All the things were quiet
- Everybody needs somebody = All the people need some person
- I looked for it everywhere = I looked for it in all the places
- Everybody is happy