问题
选择题
__________ did your uncle leave his hometown ?
He _________ for nearly 20years .
A．When , has left
B．When , has been away
C．How long , has left
D．How long , has been away
答案
答案：B
题目分析：句意：你的叔叔什么时间离开他的家乡的？他离开有近20年了。How long ,多久提问一段时间，与它连用的要么是可延续性的动作，要么是延续性的状态。根据leave非延续性动作，可知用when提问。for nearly 20years近20年，一段时间，leave对应的延续性状态是be away.故选B。