出発時間を決めましょう。

N4 出発 shuppatsu departure, start N5 時間 jikan time N1 決 ketsu decision, vote

N5 出 shutsu, sui / de.ru, -de, da.su, -da.su, i.deru, i.dasu exit, leave, go out N4 発 hatsu, hotsu / ta.tsu, aba.ku, oko.ru, tsuka.wasu, hana.tsu departure, discharge, publish N5 時 ji / toki, -doki time, hour, temps N5 間 kan, ken / aida, ma, ai interval, space, intervalle N3 決 ketsu / ki.meru, -gi.me, ki.maru, sa.ku decide, fix, agree upon

N5 〜ましょう mashou Invitation suggestion or joint proposal form, equivalent to let us do something 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