Generate a sentence that answers this question: "Which uses gills to breathe?".

Answer: gills are used for breathing water by aquatic animals

Generate a sentence that answers this question: "Oceans cover 70% of the surface of what?".

Answer: oceans cover 70% of the surface of the earth

Generate a sentence that answers this question: "Which of the following is more accurate?".

Answer:
as state of matter changes , mass will not change