“变数”的英语？

两性之争也出现了新的变数。The battle of the sexes also took a new twist.载人宇宙飞行的前景看上去充满了越来越多的变数。The future for manned space flight is looking increasingly uncertain.整个局势中的变数是东欧。The wild card in the picture is Eastern Europe....

“变数”的反义词：常数。...