In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.

[Q]: Question: What holds ionic and covalent compounds together? Answer: electrostatic attractions
[A]: Electrostatic attractions holds ionic and covalent compounds together.


[Q]: Question: What do craters and rifts become when the fill with water? Answer: lakes
[A]: Craters and rifts become lakes when they fill with water.


[Q]: Question: What is the most abundant type of biological entity on the earth? Answer: viruses
[A]:
Viruses are the most abundant type of biological entity on the earth.