I babysit a little boy that is 2 1/2. I have only heard him say about 20 words clearly. I've noticed he doesn't like to make eye contact when you talk to him, and when he wants something all he does is points at it instead of asking. I can't even get him to say yes or no when I ask him if he wants something to drink. I'm just trying to decide if I need to somehow talk to his parents about it or just let it be.

At that age he should be forming simply sentences, at least. It's possible that he's just not talked to at home. It's also possible that there's a developmental problem that speech therapy, or another form of therapy, can help.

The thing is, as the babysitter, it's really not your place to say anything. You can try working with him she you're watching him. Things as simple as sitting down and reading a picture book with him and pointing out some of the things in the pictures and trying to get him to repeat you, or telling him to use his words when he wants something, may help. Anything else is really up to his parents.

If you try to bring it up, they will probably see it as you questioning their parenting. Not only will they be upset, but it's likely that they'll look for a different sitter.

At the age of 2 and a half some children speak a lot and some don't, they all start doing things at their own pace, you could do as above person has suggested by showing him pictures in a book telling him what they are and asking him to relay this to you.

Or just let him decide to talk at his own pace. You may find if you talk to him often then he will begin to talk back.

It is very commendable of you to be concerned about this child however his parents may not be of the same mind, and may interpret your opinions in the wrong way, so perhaps it is best you keep your thoughts to yourself, unless of course you're on good terms with the parents.

Myself I would be grateful if I were using a child minder and she/he were so concerned about my child, however not many parents would be so inclined.

I have always talked to children in the same manner as I would talk to an adult.
No baby talk. No squeeky high voice. Just simpler words but straight forward speech.
It has always worked well for me,