Question

Europeans always hold their fork in the left hand, ________Americans switch it between their left and right hands.

A．before	B．because
C．while	D．since

Answer 1

C

while意为“然而”，此处表示对照对比关系。句意：欧洲人总是用左手握叉子，但是美国人总是左右手交换着使用。before意为“在……之前”引导时间状语从句；because引导原因状语从句，意为“因为”；since意为“既然”引导原因状语从句，意为“自从”引导时间状语从句。