Some house plants grow better if placed near a window with plenty of sunlight others pref

问题补充：

Some house plants grow better if placed near a window with plenty of sunlight others prefer to be in a more shaded spot.

A. unless

B. since

C. when

D. while

答案：

A. unless

B. since

C. when

(答案→)D. while

解析：考查连词：A. unless除非B. since自从，既然 C. when 当…时候，既然D. while当…时候，然而，虽然，句意：一些室内植物如果放在有充足的阳光的窗户旁边就长得很好，然而有的喜欢在有阴凉的地方。选D。