互调干扰需满足：一定的频率组合关系、（）和相关台站同时工作。

阅读理解。

     Sally and her brother Jim are traveling to Europe. They like to travel by train or by ferry because they can

see a lot of beautiful sights in different places and they usually travel at night. Now they are sitting in a train.

It's dark outside and others are sleeping. The window near their seats is open. Sally is looking out of the

window. She can see some thin clouds in the sky. The Moon behind the thin clouds is very beautiful and bright.

She enjoys the Moon very much and doesn't feel tired. Jim is sitting near her and sleeping. Tomorrow they will

take a ferry to Paris.

1. Sally and Jim are traveling ______.

A. by ferry

B. by train

C. by plane

D. by bike

2. Why do they like to travel by train or by ferry?

A. Because it's very cheap.

B. Because they can travel very fast.

C. Because they can enjoy the beautiful sights.

D. Because they can sleep in a train.

3. Sally can see ______ in the sky.

A. some clouds and birds

B. some clouds and the Moon

C. the Moon and a plane

D. some snow

4. Jim is ______.

A. looking out of the window

B. enjoying the Moon

C. sleeping

D. singing

5. Sally and Jim will reach ______ tomorrow.

A. Paris

B. London

C. Rome

D. Beijing

哪些措施可以防止设备腐蚀？

会计凭证不得外借，其他单位如因特殊原因需要使用会计凭证时，经本单位会计机构负责人批准，可以复制。( )

磨矿细度过粗或极细都对浮选不利。

阅读下面短文，回答下列问题。
“韦编三绝”是说孔子读《易》次数之多，竟把编联简策的编绳翻断了多次。此语最早见于《史记·孔子世家》。对“韦编”的“韦”如何理解新版《辞海》的解释是：“韦，熟牛皮。古代用竹简写书，用皮绳编缀，故曰韦编。”这种说法其实是错误的。其一，现代的形声字古代常常写作假借字，汉代文献中此例不胜枚举。汉代许慎《说文》有“经，织从丝也”。许慎所用的“从”字，即今之形声字“纵”字的假借字。我们既知纵字在汉代实写作“从”，那么我们把汉人(司马迁)写的“韦编”读作“纬编”，是合乎汉人用字常理的。纬编即编联简策的纬绳。因为古人常把纵横称作经纬，所以《说文》又称“纬，织衡丝也”。简书的竹简是纵向排列的，犹如织布帛的经线，编联简策的组绳则是横向编联的，犹如织布帛的纬线。据此，把横向编联简策的组绳称作“纬绳”、“韦编”是理所当然的。其二，古代简书并不一定是用皮绳编缀的。陈梦家在《汉简缀述》中写道：“所用以编简札为册者，多为丝纶，有时写作‘绳’，有时写作‘编’。苟勋《穆天子传》谓汲郡魏家所出‘皆竹简素丝编’，《南齐书吱惠太子传》记襄阳古冢所出《考工记》“竹简书，青丝编……”居延出土汉简册，则为麻绳。”毫无疑义，所谓“素丝编”、“青丝编”都是指的丝绳。出土简册，则木简仅见用麻绳。除了“韦编三绝”的“韦”被释为皮绳外，尚不见任何关于用皮绳编联简册的记载和实物。

作者认为《辞海》对“韦编三绝”的“韦”字解释有误，不能作为这一观点依据的一项是______。

A．把横向编联简册的组绳称作“纬绳”、“韦编”是理所当然的

B．孔子读《易》，竟然多次翻断了简策的编绳

C．既然“纵”字在汉代实写作“从”，那么把“韦编”读作“纬编”是合理的

D．因为古人常把纵横称作经纬，纬(韦)编即编联简策的纬绳