题目

完形填空 One custom that shows people's history andvalues is the way they greet one another. There are different ways of1aroundthe world. They change from the2handshake to other strangegreetings found in some countries. In the United States and Canada, a simplehandshake is common. There is an interesting story about the handshake: 3startedlong ago as a way of showing people that you weren't carrying a weapon (武器) . It is usual to shake the person's right4whilelooking him or her in the eye. Handshakes are also common in other partsof the5, including Britain and Russia. InRussia men hol化学概念在逻辑上存在如下图所示关系，对下列概念间的关系说法正确的是包含关系 并列关系 交叉关系A．纯净物与混合物属于包含关系 B．氧化反应与化合反应属于并列关系C．化合反应和分解反应属于交叉关系D．化合物与氧化物属于包含关系