Some words have different meaning in other languages. For example, an adj. ”amai/tian” means ”sweet, the taste of sugar” in both Mandarin and Japanese, but there are some other semantic meaning like ”a thin taste” and ”a not strict way” in Japanese. These differences sometimes makes student confuse. Language teachers have to pay more attention not also words' basic meaning, but also its donotation. In this paper, we will organize the meaning of ”amai/tian” between Mandarin and Japanese. And we will come up with its' teaching ways at last.