Water is very important to us. If you don’t have water for three days, you will die. We can use water for flowers, swimming, washing and many different things. We use it to cook, make electricity, put out fires and so on. We use millions of liters of water every day.
Do you know how does the water come to your home? It travels through water pipes. Some are long and wide but some are short and narrow. Then the water travels through the water pipes to the reservoirs. Then it travels through the water pipes to the river and to the special factories (we call water plants) that purify the water. When the water is purified, we can drink it. Please don’t leave garbage in the water on which we line, and keep the water clean.
10项详细解析GRE数学考试基本概念
GRE数学考点:Substitution
GRE数学备考:分数和小数
GRE数学考点介绍:Conditional
GRE数学余数考题例题
GRE考试数学学习方法:代入检验
GRE数学考点:Algebraic Expression
GRE数学备考:代数
考GRE数学满分 做好最后冲刺计划
做到两点便可取得GRE数学图表题高分
GRE数学常用结论:对立事件及独立事件概率
GRE数学考试常用术语汇总
新GRE数学策略:代入检验
GRE数学专项考试12项内容介绍
GRE数学考点题目:Adding Monomials
GRE数学基本概念+实例解析(2)
新gre数学考点介绍:Monomials
GRE数学要点
GRE数学考点:At Least Once
GRE数学:有关余数的考试题目
GRE数学常用公式表达
GRE数学备考:算术
GRE数学考点:Linear Equation of One Variable
GRE数学冲刺阶段备考分析
GRE数学疑难问题例题解答
GRE数学难题讲解20例
GRE数学符号英文表达汇总
GRE数学考点:Multiplying Monomials
GRE数学考试复习注意问题
GRE数学考点:Evaluating Expressions
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