Torah What is proper Torah learning?

Igros Moshe (YD III:87.2) Question What is proper Torah learning in Yeshiva? Answer  The mitzva of Torah study  is to learn the entire Talmud  and to to know all the Torah laws in addition to studying in depth each subject in the gemora  as well as the Rishonim and Achronim which are indespensible  even for a big Torah scholar. It is important also to understand the reasoning and the halacha as well as the explanations given by the Rosh Yeshiva