her mother has been a party member for three years =her mother ________the party

问题描述:

her mother has been a party member for three years =her mother ________the party

Her mother has been a party member for three years.= Her mother (joined) the party three years ago.她妈妈三年前入了党.这是由现在完成时变为一般过去时.join是短暂性动词,在完成时中用be a member of来替换....