8.The enery source on Voyager 2 is not a nuclear reactor, in which atoms are actively broken apart; rather a kind of nuclear battery that uses natural radioactive decay to produce power.

(A)apart; rather

(B)apart, but rather

(C)apart, but rather that of

(D)apart, but that of

(E)apart; it is that of

正确答案是B.用考点not....but rather 和分号前后必须是完整的主谓结构 能选出正确答案.

但有个问题是.逗号+ but rather +后面部分    不是个完整的主谓结构啊??这样可以吗?

not A,but rather B,  A,B平行比较

B是一个名词啊，后接一个定语从句嘛，that用放射性自然衰变来产生能量