I really want to be a scientist. I think the scientist is the best job for me. A good scientist can make the world change a lot. If I become a scientist, I will make the desert be coverd with green trees and grasses, make the war never take...

March 12th is Tree Planting Day. This year our school bought enough trees before that day . On that day , we didn‘t had classes . The teachers and our classmates planted trees around our school. We began to planted trees as soon as we got...

March 12th is Tree Planting Day. This year our school bought enough trees before that day . On that day , we didn‘t had classes . The teachers and our classmates planted trees around our school. We began to planted trees as soon as we got...

应知 一、基本概念。 分式：一般地，形如的式子叫做分式，其中A和B均为整式，B中含有字母，且B≠0。 【注意】 ①对整式、分式的正确区别：分式的分子和分母都是整式，分子可以含...

My home town My home town isevery beautiful. it stands beside a wide river and is rich in fish and rice. But in the old days it was a poor and backward little town. many people had no work. they lived a hard life. In 1949 my hometown was li...

Liu Kai is my classmate. He is a good student and always ready to help others. One day on his way to school，he saw a little girl crossing the road. A car was coming towards her quickly and the girl was too frightened to move. The car nearl...

应知 一、基本概念 命题：可以判断出它是正确的还是错误的句子叫做命题，正确的命题称为真命题，错误的命题称为假命题。 在数学中，许多命题是由题设（或已知条件）、结论两部...

Its Important to Learn English English is widely used throughout the world. So many people speak it as a second language. ()n line, youll find lots of information in English. If you dont understand English, how can you know more about the wo...

应知 一、基本概念 算术平均数：一组数据的总和与这组数据的个数之比叫这组数据的算术平均数。其计算公式为：，即：算术平均数=各数据的和÷数据的个数。 算术平均数是全部数据...

应知 一、基本概念 函数：一般地，在一个变化过程中，如果有两个变量x与y，并且对于x的每个确定的值，y都有唯一确定的值与其对应，那么我们就说x是自变量，y是x的函数．如果当x...