Trying to remember what my niece was like at two... (She's five now).
My niece is autistic like me, so knew some surprising words like names of dinosaurs, but otherwise was probably pretty normal.
One thing was a lot of copying things she heard people say or heard on TV. The worst being "Oh my god!"
But mostly it was things like "Oh no no no!" or "There they are!"
Her sentences were pretty limited overall to things like: "We are in the blue car.", "It's a diplodocus!" and "I am Hazel." So the main thing is, 2 year olds can't tend to connect sentences with "so", "because" or "and", and while they can comprehend concrete questions like "where?", "what?" or "who?", more abstract ones like "why?" or "how?" are beyond their ability. Mostly they don't ask questions so much as remark on things they see, imitate things they hear or draw attention to things they want. That said, I remember Hazel was capable of saying "Hazel happy!" and "I love [name]" (and she had a lot of love to give, she loved "Gran'ma" "Grandad" "Mammy" "Daddy" "Auntie Kate" "Luney" (the dog, Luna) and....Hazel! (on seeing herself in a mirror wearing all grandma's jewellery she exclaimed "Oh Gran'ma! I just love...Hazel!"))
Vocab-wise, they know a surprising number of names of colours, shapes, animals, vehicles etc. They just can't necessarily put them into a sentence more complex than "It's a [whatever]!" or "[object/thing] in/on [other thing]". So for example, when I showed her this illo I did for a tech conference:
Hazel called this "Stegosaurus on telly" (telly is a common British colloquialism for a TV), so you can see that there's a pretty sophisticated ability there to understand "stegosaurus", but the sentence structure is very simple. She could also say "in the water", so "ducks...in the water!" is a pretty plausible thing for a 2 year old to remark on.
One thing that was fun was if she didn't know what something complicated was called, she would combine words she did know. So one time I came to visit and I was wearing my headphones. She'd never seen headphones before, but since headphones go on your head, and she'd only seen me wearing them, she called them "Kate hat". So when she saw my brother wearing some a few days later she said "Ooh! Joe, Kate hat!" Another example was that she saw a sandcastle, and not knowing the word for one, she combined two words she did know to create "Seaside tower". I have no idea if this is a normal 2 year old thing or just Hazel, but it was super-cute.