【正确答案】正确答案：It is the technical name for the sameness relation. Two or more forms with very closely related meanings are synonyms, which are often, but not always, intersubstitutable in sentences. For example, in English "hide" and "conceal" in "He hid the money under the bed. " and "He concealed the money under the bed". Often one word may be more appropriate than another in a particular situation, e. g. "conceal" is more formal than "hide".