问题
选择题
Human facial expressions differ from those of animals in the degree ______ they can be controlled on purpose.
A．with which
B．to which
C．of which
D．for which
答案
答案：B
to which引导定语从句；which指代先行词animals,表示“对它们来说”；with which 意为“和……在一起”；of which 意为“其中”；for which 意为“为了”。