Looking for serious C&C!

First time in studio... I want to improve! Give me as much help as you can! This is for photo class, and we are allowed to use one light... How did I do?

1.

IMAGE LINK: http://www.flickr.com/​photos/kalahmarie/5599​878338/

IMAGE LINK: http://www.flickr.com/​photos/kalahmarie/5599​876628/

IMAGE LINK: http://www.flickr.com/​photos/kalahmarie/5599​862472/

these are great.

next time i wouldn't have the model where a dress the same colour as the BG in order to have some separation. other than that i think you've done quite well. a light coloured BG would have allowed for nice separation with her dark hair as well. that's my not-so-professional opinion.

lovely model.

Number 2 is really nice

let more light/exposure and set your main light a bit higher
second background/dress match
sweet model

Thanks for the help! I'll try these things when I reshoot

I like the lighting better in the first two. the light in number 3 is just a tad harsher than the first two. They look great anyhow

not bad at all, I agree number 2 is my favorite. only criticism is I'd try to raise the light up higher, the shadow from the nose makes it look like it is at eye level, which is no problem at all but I prefer a higher light on a shot like this, great job for the first time in studio!

What type of light was allowed for this shoot?