彼は忙しいかもしれないと思います。

N5 彼 kare he N5 忙しい isogashii busy N4 もし moshi if, in case, supposing N5 います imasu there is / exist (living things)

N3 彼 hi / kare, kano, ka.no he, that, the N3 忙 bou, mou / isoga.shii, sewa.shii, oso.reru, ureerusama busy, occupied, restless N4 思 shi / omo.u, omoera.ku, obo.su think, penser, pensar

N4 〜かもしれない kamoshirenai Indicates uncertain possibility, attaches to verb adjective or noun, means maybe or it may be that N5 〜と思う to omou Indicates speaker thought opinion or assumption, connects clause with mental expression N5 〜ます masu Used at the end of verbs, polite present or future form, makes the sentence more polite N4 〜し shi Indicates multiple reasons or qualities, connects clauses or adjectives, means besides that, and also N5 〜と to Indicates company, quotation, natural condition, complete list, or direct connection between elements N5 〜も mo Means also, adds another similar item, often replaces particles such as wa ga or o N5 〜か ka Marks a question, alternative, or uncertainty, appears at the sentence end or between options N5 〜は wa Marks the topic of the sentence, indicates what the sentence is about, can contrast with another element, organizes main information