He had scheduled classes at the same time as Hegel's, knowing full well that thereby he was guaranteeing for himself few, if any, students.

看红色部分。guatantee 是及物动词，接单宾语（few students）。for himself 是目的状语，提到宾语前（因为宾语内部含有一个条件状语 if any，相对较长一些，为了结构紧凑，故提前状语）。