193.
New equipment and other improvements reduced the amount of time—from eleven hours in 1982 to six in 1988—needed by workers so that they could produce a ton of steel.
B
D
A. needed by workers so that they could produce
B. needed when workers are producing
C. workers need in producing
D. workers needed to produce
E. workers need for their producing of
time后面跟的是workers needed to produce 难道定语从句后面的that可以不要么 | 
