evidence has been put forward showing that astronauts exposed to long periods of weightlessness ( ) quite severely
(A.have affected B.had affected C.have been affected D.had been affected)
it is reported that some wild animals were found ( ) in a big cave in the mountain
(A.to hidde dead B.hidden dead C.hiding dead D.hidden death)
as automation increases,the problem of unemployment will become more serious unless more men and women () the training necessary for whitecollar positions
(A.have been given B.are given C.will be given D.would be given)