A.has been upgraded
B.is upgraded
C.have been upgraded
D.has upgraded

A.on
B.in
C.from
D.with

A.the short the days become
B.the days become shorter
C.the shortest the days become
D.the shorter the days become

A.small round green
B.small green round
C.green small round
D.round small green

A.were writing
B.had written
C.wrote
D.was writing

A.due to
B.though
C.despite
D.because

A.After all the guests had come
B.By the time all the guests come
C.When all the guests will come
D.Until all the guests come

A.they want to
B.who wanted
C.want to
D.wanting to

A.advantaged
B.disadvantaged
C.advantageous
D.advantageously

A.looked up
B.sent off
C.called up
D.took off