This refers to things that are done on earth. See how you translated this in [Ecclesiastes 1:3](../01/03.md). Alternate translation: "on the earth" (See: [[rc://en/ta/man/jit/figs-idiom]])
Here the word "hearts" refers to the thoughts and emotions. Alternate translation: "Human beings are full of evil, and their thoughts are of madness" (See: [[rc://en/ta/man/jit/figs-metonymy]])
The phrase "the dead" refers to dead people. Here dead people represent the place where people go after they die. Alternate translation: "they go to the place where dead people are" or "they die and go to the grave" (See: [[rc://en/ta/man/jit/figs-nominaladj]] and [[rc://en/ta/man/jit/figs-metonymy]])