达尔文自然选择学说的理论告诉我们，生物的多样性和____性都是自然选择的结果，生物进化的方向是由____的定向选择作用决定的．

阅读下面材料，在空白处填入适当的内容（1个单词）或括号内单词的正确形式。

    In order to know a foreign language thoroughly （完全地） , four things are necessary. Firstly, we must understand the language when we hear ____ spoken. Secondly, we must be able to speak it ____ (correct) with confidence and without hesitation（犹豫）. ____ we must be able to read the language, and fourthly, we must be able to write it. We must be able to make sentences that are grammatically correct.

    There is no easy way to success in language learning. ____  good memory is of great help, but it is not enough only ____ ( memorize) rules from a grammar book. It is not much use learning by heart long list of words and ____ meaning, studying the dictionary and so on. We must learn by using the language. ____ we are satisfied with only a few rules we have memorized, we are not really learning the language. “Learn through use” is a good piece of ____ (advise) for those ____ are studying a new language. Practice is important. We must practise speaking and ____ (write) the language whenever we can.

在下列句子的空缺处依次填入成语，最恰当的一组是(        )
（1）市、区档案室是微机化管理，查阅相对容易，但在单位的档案室查找却难上加难。由于资料众多，要找到符合条件的、被丢失的部分，就像是             。
（2）剡溪，就像一位             的老人，波光里满是岁月的褶皱。那些影影绰绰的身影，渐渐地融入了历史的一场场清梦中。
（3）景区在管理帐篷客问题上不宜“一刀切”，应             ，做好配套服务，想方设法满足游客的新需求。