re all the principles practical?
I don't really know what you mean by this...
But the thing is, you are supposed to critique them based on what you have been learning this semester. I may be wrong, but you are probably supposed to discuss the 10 principles and ALSO discuss what you have learned this semester.
Because I do not have much experience in teaching English, it seems to be difficult for me to apply, compare or evaluate what Ellis has said.
You have to be able to do all that. There is no way around it! :-) Otherwise, you have not learned it.
I suggest looking on Google video to see if there is a video about them.
Also, read 5 web pages about them.
Spend some time getting deeply involved with the 10 principles. I wish I had some more useful advice!! :-)