80.
Changes in sea level are not only a result of changes in water temperature, affecting water density, but of melting glaciers as well.
(A) are not only a result of changes in water temperature, affecting water density, but of melting glaciers as well
(B) not only result from changes in water temperature, which affect water density, but also when glaciers melt
(C) are a result not only of changes in water temperature, which affect water density, but also the melting glaciers
(D) result not only from changes in water temperature, which affect water density, but also from the melting of glaciers
(E) result from not only changes in water temperature, affecting water density, but as well as when glaciers melt
81.
In the major cities of industrialized countries at the end of the nineteenth century, important public places such as theaters, restaurants, shops, and banks had installed electric lighting, but electricity was in less than one percent of homes, where lighting was still provided mainly by candles or gas.
(A) electricity was in less than one percent of homes, where lighting was still
(B) electricity was in less than one percent of homes and lighting still
(C) there were less than one percent of homes with electricity, where lighting was still being
(D) there was less than one percent of homes that had electricity, having lighting that was still
(E) less than one percent of homes had electricity, where lighting had still been
当ing做结果状语时，是不是不能修饰前面的be动词呢？求解
