Answer:
Black hole is a region of spacetime where gravity is so strong that nothing — no particles or even electromagnetic radiation such as light — can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.
Answer:
"I'm unhappy like a rainy day."
Simile.
Most times the introduction, or often times in the thesis statement.
There should be a semicolon where the comma is.
