单项选择题

According to the passage, recycling is only possible when ______.

A．it is monitored by the government
B．different collection schemes operate
C．there is enough clean material
D．there is a small amount of clean material

<上一题目录下一题>

热门试题

单项选择题

Which of the following waste is best suited to recycling

A．Empty milk cartons.
B．Textiles.
C．Potato peelings.
D．Cabbage stalks.

单项选择题

The problem of deciding at what point a baby's imitations can be considered as speech ______.

A．is not especially important because the change takes place gradually
B．is important because words have different meanings for different people
C．is one that can never be properly understood because the meaning of words changes with age
D．is one that should be completely ignored because children's use of words in often meaningless