1．The mayor of Beijing says that all construction work for the Beijing Olympics ________ by 2006.
A．has been completed B．has completed
C．will have been completed D．will have completed
解析：
by 2006表将来时间之前的动作，常与将来完成时连用。主语all construction work与complete之间是动宾关系，故采用被动语态，综合起来选C答案。
答案：C
2．More and more people are signing up for Yoga classes nowadays, _____ advantages of the health and relaxation benefits.
A．taking B．taken
C．having taken D．having been taken
解析：主语people与take advantages of之间是主谓关系，故用现在分词作伴随状语。
答案：A
