私は弟に本を貸してあげました。

N5 私 watashi I N5 弟 otouto younger brother N5 本 hon book N3 貸し kashi loan, lending, favor owed

N4 私 shi / watakushi, watashi private, I, me N4 弟 tei, dai, de / otouto younger brother, faithful service to elders, frère cadet N5 本 hon / moto book, present, main N4 貸 tai / ka.su, ka.shi-, kashi- lend, prêter, louer

N4 〜てあげる te ageru Indicates doing something for another person, attaches to the te-form verb, can sound patronizing if used carelessly 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 〜を o Marks the direct object of an action, appears before the verb, shows what receives the action N5 〜に ni Indicates destination, target, arrival point, specific time, or person receiving an action N5 〜は wa Marks the topic of the sentence, indicates what the sentence is about, can contrast with another element, organizes main information