在山区飞行时应当注意，最强的乱流出现在（） A.山谷中间 B.山的迎风坡 C.山的背

下列加点字的注音，都正确的一项是（  ）

A．褶皱（zhé）趿拉（tā）蹙（cù）缩阴翳（yì）

B．迸发（bèng）羞怯（qiè）鬈曲（juǎn） 怜悯（mǐn）

C．瞭望（liào）嵯峨（cuó） 哺育（bǔ）赊账（shē）

D．姊妹（zǐ）愧怍（zhà） 伛偻（yǔ）踮起脚（diǎn）

He has a habit of keeping his arms _____ when talking to others, which I personally think _____ impolite

to his audience.  [ ]

A. to be folded; it    

B. being folded; X    

C. folded; it    

D. folded; X

在括号里填上合适的词。 

1．一（       ）乌云    一（       ）大风    （       ）蜘蛛 

      一（       ）蝉      一（       ）房子    （       ）彩虹  

2．（       ）的空气    （       ）的青蛙    （       ）的乌云

Why does a lack of sleep cause people to gain weight().

A.Because people burn fewer calories when they are awake.

B.Because people feel hungry when they lack sleep.

C.Because their hormones stay unchanged.

D.Because people don’t exercise when they don’t have enough sleep.

擎檐柱