約束を忘れたわけではありません。

N4 約束 yakusoku promise, appointment, arrangement N5 では dewa then, well, in that case

N3 約 yaku / tsuzu.maru, tsuzu.meru, tsuzuma.yaka promise, approximately, shrink N3 束 soku / taba, taba.neru, tsuka, tsuka.neru bundle, sheaf, ream N3 忘 bou / wasu.reru forget, oublier, olvidar

N5 〜です desu Used at the end of a sentence, polite affirmative form, means to be depending on context N5 〜ます masu Used at the end of verbs, polite present or future form, makes the sentence more polite N5 〜を o Marks the direct object of an action, appears before the verb, shows what receives the action N5 〜で de Indicates where an action happens, means used, tool, cause, or material depending on context N5 〜は wa Marks the topic of the sentence, indicates what the sentence is about, can contrast with another element, organizes main information