11．It is said that tigers ________ in Asia year after year.

11．It is said that tigers ________ in Asia year after year.
A.are being disappeared B.are disappearing
C.will be disappeared D.will disappear
12.I’m going to Wuhan tomorrow.Do you have anything ____ to your mother?
A.to take B.taken C.to be taken D.taking
13.Take it easy.There is nothing ______.
A.to worry B .to be worried
C.to be worried about D.to worry about
14.Your new computer will soon become outdated,because technology _______so fast.
A.is developed B.is being developed
C.has been developed D.will developed
15.I won’t go to the party unless _________.
A.invited B.being invited
C.be invited D.inviting
16.The problem ________ last week is very important.
A.was discussed B.discussed
C.being discussed D.be discussed
17.We should keep the animals from ________.
A.be endangered B.endangering
C.being endangered D.endangered
18.There are no rivers _______out of the Dead Sea.
A.flowed B.flowing
C.being flowed D.be flown
19.This place has been destroyed.So there is no bamboo ______ for pandas to feed on.
A.left B.leaving C.leave D.be left
20.All the preparations for the task ________ ,and we are ready to start.
A.completed B.complete
C.had been completed D.have been completed

11.B(year after year,表示正在进行发生的趋势)
12.A(have sth.to do )
13.D(worry about,固定短语搭配,be nothing to do)
14.A(正在进行发生的事,句子中的主语technology与谓语动词develop不存在被动)
15.A(被动语态,当主语与从句的主语一致时,省略从句主语I'm be )
16.(后置定语,last week,过去式,选B)
17.C(keep sb./sth.from (doing) sth,这里用被动语态表示处于没有危险之中)
18.B(首先是非谓语,再者river与动词flow之间不存在被动,故选A)
19.A(被动语态做后置定语)
20.D(句子从意思上说本身存在一个先后关系,其次主语preparations与动词complete又存在被动关系,根据后半句谓语动词are来断,时间段为到现在为止,所以用现在完成被动时)
自己做的,标了注解,希望你能看明白...