Table tennis, also known as ping-pong, is a sport in which two or four players hit a lightweight ball back and forth across a table using small rackets.
请问，为什么说这里的in which不可以用that代替呢？ (这个in which是充当从句的哪个部分？)
这里的 in which = and in the sport,所以这里的in which不可以用that代替。
