题干

下列有关实验现象的描述正确的是

A:硫在氧气中燃烧产生淡蓝色的火焰

B:磷在空气中燃烧产生白色烟雾

C:氢气在空气中燃烧产生黄色火焰

D:硫酸铜溶液滴入氢氧化钠溶液中产生絮状沉淀

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D

同类题5

阅读理解

    So long as teachers fail to distinguish between teaching and learning, they will continue to undertake to do for what only children can do for themselves. Teaching children to read is not passing reading on to them. It is certainly not endless hours spent in activities about reading. Douglas insists that "reading cannot be taught directly and schools should stop trying to do the impossible."

    Teaching and learning are two entirely different processes. They differ in kind and function. The function of teaching is to create the conditions and the climate that will make it possible for children to devise the most efficient system for teaching themselves to read. Teaching is also a public activity: It can be seen and observed.

    Learning to read involves all that each individual does not make sense of the world of printed language. Almost all of it is private, for learning is an occupation of the mind, and that process is not open to public scrutiny. If teacher and learner roles are not interchangeable, what then can be done through teaching will aid the child in knowledge. Smith has one principal rule for all teaching instructions. "Make learning to read easy, which means making reading a meaningful, enjoyable and frequent experience for children."

    When the roles of teacher and learner are seen for what they are, and when both teacher and learner fulfill them appropriately, then much of the pressure and feeling of failure for both is eliminated. Learning to read is made easier when teachers create an environment where children are given the opportunity to solve the problem of learning to read by reading.