1, Mark usually refers to artificial marks or marks, and also refers to natural marks or features that are different from other things. For example, marking an article or leaving a stain on clothes can be called marking. As a verb, mark means to mark or score.

2. Signs refer to the signs or signs of something recognized by people, and can also indicate the signs of a certain situation. For example, traffic signs or weather signs can be called signs. As a noun, sign can refer to not only signs or symbols, but also phenomena or omens; When used as a verb, sign means to sign or sign.