- INTRODUCTION
Clause is a group of words that includes a subject and a verb. Requirement of the clause there are subject and object that make up a sentence. Clauses have two kinds. They are independent clause and dependent clause. Independent clause is clause that can stand alone as a sentence and dependent clause is clause that can’t stand alone as a sentence. It can’t stand by itself because not express a complete thought. Fuad (2002:151) states that clause is a set of words that contains a subject (subject sentence) and a predicate (term sentence).
In general, dependent clause in sentence has specific information to explain independent clause. Dependent clause is divided into 3 types. The first is Noun Clause, the second is Adjective clause, and the last one is Adverbial clause. Adverbial clause is a dependent clause that functions as an adverb and provide information about the verb, adjective, or adverb which are in the independent clause with it is capacity to answer the question how, when, where, why, or to what degree.
 Adverbial clause is one part of grammar that is learned by students. In addition learning about adverbial clause students also learn about noun clause and adjective clause also, Adverbial clause is learned in Senior High School. Senior High School Students learn about Adverbial clause when they are at the second grade. They learn about it as additional grammar. It is important to learn because when students learn about adverbial clause, students should know about structure of sentence, what tense is used in the sentence? And translate the sentence is too.
The main purpose of Adverbial clause is comprehension. Students’ Comprehension of Adverbial clauses is students able to answers the questions about them. Students can know what kinds of Subordinate clause that consisted in a complex sentence.
As, the writer experiences was in Teaching Practice Program (PPL) in SMK Telkom Sandhy Putra Medan at second grade. The writer had interviewed the students about their motivation in learning English. The writer found that so many students had low in motivation. Many students said that they don’t care about English and have no attention to the process of teaching. After interviewing the English teacher and some students, it can be concluded that students get difficulties in comprehending adverbial clause because they have lack of vocab and they still do not have good attention in studying English, because from the first level with the previous teacher they only been taught about grammar, not fun activities. The result is they were getting bored and they have less motivation on it. The failure of the students in studying English is happened because the students do not enjoy their lesson.
Based on the curriculum of SMA/SMK in second grade, the students were expected to comprehend the adverbial clauses and also have ability to do communication both in written and oral language to advice functional and informal literacy. The writer found the problem in the school because there was a gap between reality and expectation. The researcher found the problem where students were still lack in grammar. Due to adverbial clause which included a grammar is difficult to comprehend by them. This situation was different with basic competencies or indicator in curriculum.
In this research the writer taken three researches that was conducted by the previous researchers to strengthen this research. Moreover, the first previous researcher is Boyer (1991) was investigating about statistical studies adverbial clause. This study explained about clauses will be concerned with the adverbial clauses. This study stated that attention will be given to the conjunctions or conjunctive relative phrases used to introduce the clauses, to the moods used, and to the give statistical information at every level, so that the students may begin to appreciate the relative magnitude of each structure.
In Addition is Hinkel (2002) investigated the research about presents a qualitative analysis of deictic, modifying, and intensifying adverbials, as well as several semantic clauses of adverb clauses, and compares their median frequency rates in academic essays written by first- year Nation students and academically-advanced Non Nation School students. This study was focus on Notion Student and Non Nation Student uses of twelve semantic and syntactic classes of adverbials. They are time adverbs, place adverbs, manner adverbs, amplifiers, emphatic adverbs, downtoners, cause clauses, concession clauses, condition clauses, conditional clauses, purpose clause, other types of adverb clauses, and reduced adverb clauses.
This was supported by Haegeman (2006) who did investigate the research about main clause phenomena and the derivation of adverbial clause. The purpose of the study is concerned with the syntactic derivation of adverbial clauses. A movement analysis of adverbial clauses allows us also to account for a number of other such phenomena both in English and in other language.
Based on the explanation above, the writer was interested to conduct the research about Analysis Student’s Comprehension of Adverbial Clauses at SMK Telkom Sandhy Putra Medan. The writer wanted to know the student’s comprehension in Adverbial Clause because before that never researcher research about analysis adverbial clause in student. This study would be conducted to know the students’ comprehension in adverbial clauses. If the will be conducted, students should will know how their comprehension about adverbial clause. Teachers will know how good the method was that they taught in adverbial clause before from students score of adverbial clause, the writers can found how students comprehend about adverbial clause and found a good alternative method to improve students’ comprehension of adverbial clause. If the research was not to be conducted the students, teacher, the school, and the writer would not know the weakness in study of adverbial clause.