If i am a graduate student,i would like to specialize in one subject; if i am an undergraduate student, i would like to take classes in many subjects. The reasons are below.
Firstly, it bases on one rule of human being's memory. to major in one subject means that a student should have many background to understand it deeply; but to take classes in many subjects is concerned to broaden a student's horizons, and study each subject not as deep as the one specialized in one subject. according to men's memory, we always remember firstly some concepts of many subjects,then with interests, we learn those concepts which are used in one field. at last, we create some things after deep-learning.
Secondly, from my personal experience, i have seen some people of those who take many courses when they are graduate and other students who specialize in only one major in their undergraduate stage. Take my sister for example, she liked mathematics when she studies in college,and was often absent from other subjects to have mathematics lessons. But after her undergraduation, she found that she no longer loved the math as she had had. but except it ,she did not know what field she liked because she knew other fields very little. Another example happens to my friend, jane,she is a graduate student now , majors in the law, but as she did not learn other lessons when she studies in college, she has to learn them for understanding the law deeply at her graduate stage.
Finally, though there are some people who can take classes in many subjects in college and other who can major in only one when he or she is an undergraduate student, doing them well at any stage , for the general, it is better to do things at its proper place at the proper time. And the subject is the thing which need to be taken according to mankind's nature.