I'll introduce the basic rules of Japanese grammar, part 3. 9) The difference between "です desu" and "あります arimasu" is that desu is a polite assertive expression of " だ da", not used independently, but mainly works as a part of a predicate, and "arimasu" represents the existence of things, events, and so on.  ○ げんきです Genki desu (I'm fine) × げんきあります Genki arimasu (There is fine) 10) In Japanese, the word order does not change like in English when making interrogative sentences. (× Do they ?) Instead, the sentence ends with a word called a final particle ("か ka", etc) at the end of the sentence, or with an increased intonation at the end of the sentence without the particle. Review: The assertive "です desu" used at the end of a sentence connects to nouns and adjectives, but not to verbs. (Exception: dictionary form of verb + "の no”or "こと koto" etc, + "です desu") A verb is connected to the auxiliary verb, " ます masu". Are you an only child?? あなたは一人っ子ですか？（あなたは、ひとりっこですか？）＝ひとりっこ？< N + ですか Which you prefer to it? どれがいいですか？＝どれがいい？　< i-adjective + ですか Are you ok? 大丈夫ですか？（だいじょうぶですか？）＝だいじょうぶ？< na-adjective + ですか Will you come to the office tomorrow? 明日、事務所に来ますか？（あす、じむしょにきますか？）＝あす、じむしょにくる？ = 明日、事務所に来る ”んです” か？ < before “です”, “の” becomes “ん “ = 明日、事務所に来る “の”? 11) Here's how to make a negative sentence in Japanese. The negative form of “です desu”: "（では）ありません", “（では）ないです”, “（じゃ）ありません” or “（じゃ）ないです” The negative form of “あります arimasu”: "ありません", or “ないです”. I'm not a teacher./ I don’t like oysters. 私は先生ではありません <Noun + ではありません, etc 私は牡蠣が好きではない < na-adjective + ではない, etc This problem is not so difficult.　< i-adjective +”く ku” + ありません or ないです この問題は、それほど難しくないです。