Should my daughter be saying sentences yet?

She will be 2 in may and she understands just about everything and shee says a lot of words and repeats them but she can't say sentences yet. The most she says is "I want bottle" or juice or chips or something like that. When she wants something like 2 wash her hands she will just come up 2 me and just say hands or if she wants 2 watch a show she will say dora or wow wow wubbzy or wutever show she wants. She knows how 2 count to ten and she does everything we tell her but I feel like she should be saying sentences by now or is this normal?