对于钢筋混凝土用砂，其氯离子含量不得大于0.06%。

下列说法错误的一项是 [ ]

A．“高树与低树俯仰生姿”，这句话精练而形象，它写出了俯下的高树枝和仰起的低树枝交相辉映的情景，它有动态，给人以层次感。

B．“不但形式优美，而且结构坚固”和“不但结构坚固，而且形式优美”两句相比较，只是排列顺序不同，意思完全一样。

C．说明文是客观说明事物的一种文体，目的在于给人以知识，就说明的内容看，一般可分为说明事物和阐明事理两类。

D．语调是指说话的高低、快慢、轻重、停顿等变化。不同的感情可以在语调的变化中表现出来。

Mr. Zhang once taught in a remote village in Anhui province as a volunteer, _______was accessible only on foot.

A．where

B．which

C．that

D．what

FREE $ 10 Gift Card with ANY Purchase at CVS

September 4, 2013 by Michelle

New Plink members are invited to join and make any purchase at CVS to get a $10 gift card from your choice at places like Amazon.com, Target, Walmart, Kohls, Starbucks and more!

Just sign up with Plink, then make your purchase. You’ll receive 1,000 points in your Plink account --- enough to redeem (兑换) for a $10 gift card!

※ New Plink members only, one sign-up bonus per person.

※Plink Member must link a credit or debit card and make a purchase at CVS by Sunday, 9/15 11:59 EST.

※ Purchase is necessary (after the member links a credit/ debit card to their Plink account) to qualify for the bonus 1,000 Plink Points by Sunday, 9/15 11:59 EST.

※Bonus 1,000 Plink Points will be awarded within 7 business days of the transaction posting date.

※ CVS purchases that occur on 9/16 or later will not qualify the bonus.

I happen to love Plink because they make it easy to earn without doing anything extra!

小题1:What is the first step to get the gift card?

A．Link a credit or debit card.

B．Make a purchase at CVS.

C．Open a bank account.

D．Sign up with Plink.小题2:CVS customers can get the gift card when their purchases happen on _________.

A．9/14/2013

B．9/16/2013

C．9/17/2013

D．9/18/2013小题3:Which of the following statements is true?

A．Goods at CVS are always sold at discounted rates.

B．New Plink members have the chance to get two gift cards.

C．The bonus is enough to be exchanged for a $ 10 gift card.

D．The bonus can be sold for $ 10 whenever you like.

寂静胸仅见于非常严重哮喘发作患者。

教师的职业角色有哪些试做简要的说明。