Bob wants to be a teacher.He has to learn (make; making; to make) his classes interesting.
问题描述：
Bob wants to be a teacher.He has to learn (make; making; to make) his classes interesting.
答
选 to make
learn to do sth 是“学习做某事”的意思.所以毫无疑问选to make
后面一句的意思是他得学习如何让自己的课堂变得有起来.