When you tread on the earth, you walk on it. The next time your pal thinks you have it too easy, you might ask him, “Why don’t you tread in my shoes for a day?”
Tread usually implies stepping with force, but it can also simply mean placing your feet, one after the other, on the ground. You might try to tread lightly on the moss in the backyard so you don't damage it. Tread is also a noun that means the mark that a tire leaves on the ground, or the actual grooves on the tire. You might be relieved that the tread marks at the crime scene didn't match your brother's truck after all.