彼はもう家に帰ったに違いありません。

N5 彼 kare he N5 もう mou already / more N5 家 ie house / home N3 違い chigai difference, distinction, mistake

N3 彼 hi / kare, kano, ka.no he, that, the N4 家 ka, ke / ie, ya, uchi house, home, family N4 帰 ki / kae.ru, kae.su, oku.ru, totsu.gu homecoming, arrive at, lead to N3 違 i / chiga.u, chiga.i, chiga.eru, -chiga.eru, taga.u, taga.eru difference, differ, différence

N4 〜に違いない ni chigai nai Indicates strong certainty based on evidence or deduction, attaches to verb adjective or noun, means must surely be N5 〜ます masu Used at the end of verbs, polite present or future form, makes the sentence more polite N5 〜もう mou Indicates recent completion or change, equivalent to already, shows action completed before now N5 〜に ni Indicates destination, target, arrival point, specific time, or person receiving an action N5 〜も mo Means also, adds another similar item, often replaces particles such as wa ga or o N5 〜は wa Marks the topic of the sentence, indicates what the sentence is about, can contrast with another element, organizes main information