题目

下列各式中：①；②；③；④；⑤；⑥分式有（ ） A．1个  B．2个   C．3个  D．4个 答案：B【考点】分式的定义． 【分析】判断一个式子是否是分式，关键要看分母中是否含有未知数，然后对分式的个数进行判断． 【解答】解：①分母中含有π，是具体的数，不是字母，所以不是分式； ②分母中含有字母a，是分式； ③是等式，不是分式； ④分母中没有字母，不是分式； ⑤分母中含有字母Carnival today is an international experience, creating a 【1】 (relax) atmosphere. To understand 【2】 (it) origin and meaning, we need to look at the history of America. The 【3】(arrive) of Europeans in America, and the opening of huge farms and plantations meant there was a need for labor force. This was how the slave trade began. For more than two hundred years, millions of black people were taken 【4】force from Africa and shipped to the New World, 【5】 there were mainly British and French landowners.【6】 (Nature), the Europeans also imported their own festivals. So the slaves【7】 (force) to watch as the masters celebrated carnival. Then the slaves began to hold their own carnival celebrations, imitating and making fun of their masters. But their own traditions were continued: They walked round a village with their faces 【8】(paint) white, wearing masks and singing.【9】 the slave trade was abolished in 1838 the former slaves look over the carnival, which became a celebration of freedom.With the passing of lime, the white people began to participate in the carnival, too. And they were welcomed by their former slaves. Carnival became 【10】way to unite different communities, and has become a celebration of life itself.