In order to make our city green, ________．
A.it is necessary to have planted more treesB.many more trees need to plantC.our city needs more treesD.we must plant more trees在线课程D
解析：
此题考查动词不定式的逻辑主语。句意：为了绿化我们的城市，我们必须种植更多的树。显然，“绿化城市”的动作是句子的主语发出的，所以只能是D项。本句可改为：We must plant more trees so that we can make our city green.