私は一度富士山に登ったことがあります。

N5 私 watashi I N4 一度 ichido once, one time N5 山 yama mountain N5 ことがあります koto ga arimasu have done before / sometimes happens

N4 私 shi / watakushi, watashi private, I, me N5 一 ichi, itsu / hito-, hito.tsu one, one radical (no.1), un N4 度 do, to, taku / tabi, -ta.i degrees, occurrence, time N3 富 fu, fuu / to.mu, tomi wealth, enrich, abundant N1 士 shi / samurai gentleman, scholar, samurai N5 山 san, sen / yama mountain, montagne, montaña N3 登 tou, to, dou, shou, chou / nobo.ru, a.garu ascend, climb up, monter

N3 〜ことがある koto ga aru Indicates past experience or occasional occurrence, attaches to a verb, means have done before or sometimes happens N5 〜ます masu Used at the end of verbs, polite present or future form, makes the sentence more polite N5 〜が ga Marks the grammatical subject, highlights new information, can also show slight contrast in some sentences N5 〜に ni Indicates destination, target, arrival point, specific time, or person receiving an action N5 〜と to Indicates company, quotation, natural condition, complete list, or direct connection between elements N5 〜は wa Marks the topic of the sentence, indicates what the sentence is about, can contrast with another element, organizes main information