Definition: In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.

Positive Example 1 -
Input: In early work , Rutherford discovered the concept of radioactive half-life, the radioactive element radon, and classified three types of radiations: alpha, beta and gamma radiation .
Output: Rutherford discovered the radioactive half-life, the chemical element radon, and the three parts of radiation which he named Alpha, Beta, and Gamma .

Positive Example 2 -
Input: The Inheritance Cycle is a tetralogy of young adult high fantasy novels written by American author Christopher Paolini.
Output: The Inheritance Cycle is a series of fantasy books written by Christopher Paolini.

Negative Example 1 -
Input: Boryla was not in the 1952 playoffs.
Output: Boryla did not participate in the 1952 playoffs.

Negative Example 2 -
Input: The population in China increased to around 2,000 in 2005.
Output: By 2005, the population decreased to about 2,000.

Now complete the following example -
Input: The " population growth rate " is the rate at which the number of individuals in a population increases in a given time period , expressed as a fraction of the initial population .
Output: 


Output: Population growth is the rate at which a population grows or expands .