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.

Input: Consider Input: The atomic radius of a chemical element is a measure of the size of its atoms , usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons .

Output: The atomic radius of an element is the distance between the nucleus and the edge of the electron cloud .

Input: Consider Input: It consists of a bulb containing mercury attached to a glass tube of narrow diameter ; the volume of mercury in the tube is much less than the volume in the bulb .

Output: The volume of mercury in the tube is much less than the volume in the bulb .

Input: Consider Input: The Civil Registry and Identification Service is the Chilean public service in charge of registering civil statuses of persons and other issues which , by law , it has to register .
Output: The Civil Registry and Identification Service is an institution for public service in Chile .