1,There are many different cycles in nature, such as the cycle of seasons.自然界有许多不同的循环，如季节的循环。
2,A cycle is a series of events that repeat, such as the daily cycle of light and dark.循环是一系列重复发生的事件，如每日的光明与黑暗的循环。
填空题：The number of times a cycle repeats itself within a period of time is its frequency一个周期在一段时间内重复的次数就是它的频率。
3,To evolve means to change or improve over a period of time.进化意味着在一段时间内改变或改进。
4,In biology, the theory of evolution says that advanced life forms such as humans have evolved from lower forms of life.在生物学中，进化论认为，高级生命形式，如人类，是从低级生命形式进化而来的。
填空题：According to science we have all evolved from simple one-celled organisms根据科学，我们都是从简单的单细胞生物进化而来的。
5,A force of attraction brings two objects closer together, such as the force of gravity.引力使两个物体更靠近，如重力。
6,A force of repulsion pushes two objects away from each other, such as the force between two electrons.斥力把两个物体相互推开，例如两个电子之间的力。
填空题：If two people are attracted to each other, they want to be together.如果两个人互相吸引，他们想在一起。
7,To transform means to change from one form into another.转换意味着从一种形式变成另一种形式
8,A transformation occurs when an object takes on a new appearance or structure.
填空题：In marriage , a wifes attempt to transform the behavior of her husband is often unsuccessful在婚姻中，妻子试图改变丈夫的行为往往是失败的。
9,To inherit something means to get it without having to ask or work for it.继承某种东西意味着获得它而不必要求或为之工作。
10,A child from a very rich family may inherit a lot of money.一个富裕家庭的孩子可能会继承很多钱。
填空题：He inherited a large fortune when his parents died so he doesn't have to work anymore .他父母去世后继承了一大笔财产，所以他不用再工作了。
后面测验：
①The time it takes for a cycle to repeat itself it its period.[翻译] 一个循环重复所花费的时间就是它的周期。
②Life forms evolve because they have to adapt in order to survive.生命形式的进化是因为它们必须适应才能生存。
③Gravity is a force of attraction between two objects with mass.引力是两个有质量的物体之间的引力。
④Over a period of time,the process of evolution can transform the appearance of species of life.经过一段时间，进化的过程可以改变生命物种的外观。
⑤Eye and hair color are inherited traits.眼睛和头发的颜色是遗传的特征。
⑥A good leader can transform an unsuccessful company into a successful one by changing how it is organized.一个好的领导者可以通过改变公司的组织方式把一个不成功的公司转变成一个成功的公司。
