What r the digestive enzmes in the small intestine?

Describe the structur and function of the alveolus?

This is a type of homework question not suited for here, since the answer is easily found in any reference book, textbook, or on wikipedia.

I agree with joypulv. If you had those homework questions, you are required to do them. You are fooling yourself when you ask others to do the work for you.

These are intended for you so that you strengthen your understanding in the subject, and revise your classes, notes, textbooks if necessary.

For your question, at what stage of the digestion process did you reach? What are the types of food that are left to be digested? What are the enzymes that are required then?

Do you know what is an alveolus? Do you know it's shape? Why it is as such? Where they are found and used for? These will greatly help you deduce the function.