He is using that coat from winter to spring.

You need to use your head to solve this problem.

He is my friend.

This is my new bag.

This is the book that I am reading.

Understanding the algorithm of the regression tree is difficult.

Reflexive verbs are used to express actions where the subject is acting on itself.

Using tail recursion can sometimes improve the performance of a program.

This program has recursivity.

This problem can be solved with a recursive approach.