Nowadays, in language teaching, it is necessary for teachers to define different language components in their courses for students; due to that, in this essay, mainly syntax as part of grammar structure will be clarified. According to Givón (2001), learners think there are no differences between grammar and syntax, and both have the same functions, but when significantly each of them is discussed, different features of them being explored, obviously; in language, the syntax is the functional part of grammar had believed (Huddleston, 1984). Not only, these differences can't be easily recognizable, but also various elements divided grammar and syntax into two different components of language, although each language component has an inter-related relation among other components. First of all, this essay will be defined grammar and syntax definition, and briefly, the role of other components will be mentioned, then grammar and syntax will be discussed in detail.