According to school grammar, the underlined parts in below sentences are regarded as adverbial clauses. But this thought has many problems. 비가 오기 때문에, 길이 질다. pika oki ttaemune, kili jilda 비가 오는 가운데, 행사는 예정대로 열렸다. pika oneun kaunte, haengsaneun yeojeongdaero yeolryeossta It is known that N, V, A, and P are nucleus in sentence. In Korean, a determiner modifies noun, and adverb modifies verb. Also, postposition plays a role as nucleus. We can find examples as follows: ‘그 집’, ‘천천히 달려.’, ‘매우 예뻐.’, ‘집에’. Therefore, Korean, SOV language, belongs to head- final language. On the other hand, Thai belongs to head- initial language, meaning head comes ahead, dependents come back. As a result, Thai belongs to SVO. But even though Thai and English are the same SVO languages,English is different from Thai. In English, head comes back(ex: the book / Uncle’s house), or front(ex: House of uncle / to the school). In an opinion of language typology, it is not difficult for ‘비가 오기 때문에’ to be adverbial phrase. ‘비가 오-’ becomes nominal clause ‘비가 오기’ after ‘-기’ adds to it, and ‘비가 오기’ modifies N‘때문’, successively NP ‘비가 오기 때문’ in help of adverbial case particle ‘에’ becomes to adverbial phrase. This is explaining way that head moves to right. Also ‘비가 오는 가운데’ is not adverbial clause, but just NP phrase,and adverbial phrase, I suppose. ‘비가 오-’ becomes ‘비가 오는 ‘ in help of determiner ending ‘-는’, and then ‘비가 오는’ modifies N ‘가운데’. Therefore ‘비가 오는 가운데’ is NP phrase. And even if it has not additional adverbial case particle ‘에’, it becomes background of ‘행사는 예정대로열렸다’, so it is adverbial phrase syntactically.