如图两条通电直导线平行放置，长度为L₁的导线中电流为I₁，长度为L₂的导线中电流为I₂，L₂所受L₁的磁场力大小为F，则L₂所在处由L₁ 产生的磁场的磁感应强度大小为（   ）

《猴王出世》选自我国古代杰出的长篇神话小说____，作者是____代的____。小说主要讲述了____的故事，主要人物有____等。你最喜欢的人物是____，原因是____。

给下列划线字选择合适的解释。

①如愿如诉____

A.适合；按照。  B.如同。  C.表示举例。  D.表示超过。

②趁其不备____

A.利用（时间、机会）。  B.富有；拥有。  C.追逐；赶。

Complete the following passage with the words or phrases in the box. Each can be used only once.(将下列单词或词组填入空格，每空格限填一词，每词只能填一次)

 Today I'm going to talk about rainforests. Are you  ____    with them? They're interesting and exciting places! Many kinds of the world's plants and animals live in the rainforests.

 However, rainforests are____ now---they are disappearing very fast because they are cut down or burnt every day. As a result,   ____  animals and plants are dying out.

 Maybe you have never been to a rainforest, so why should you protect them  ____  ?  Rainforests are important to everyone. They are important because the plants in the rainforests make oxygen . We need oxygen to breathe.