问题
选择题
Robert is away. He _______ America since last week.
A．has been to
B．has joined a club in
C．has studied in
D．has become a manager in
答案
答案：C
题目分析：句意：Robert走了。他从上个星期开始就在美国学习了。时间状语是since last week，因此要选延续性动词。Have beem to“表示去哪后并已回来了”；join和become都是点动词，故选C。