彼のことがずっと不安でしかたない

N5 彼 kare he N3 ずっと zutto for a long time, all along, much more N3 不安 fuan anxiety, uneasiness N5 ない nai there isn't, doesn't have

N3 彼 hi / kare, kano, ka.no he, that, the N4 不 fu, bu negative, non-, bad N4 安 an / yasu.i, yasu.maru, yasu, yasu.raka relax, cheap, low

N4 〜し shi Indicates multiple reasons or qualities, connects clauses or adjectives, means besides that, and also N5 〜が ga Marks the grammatical subject, highlights new information, can also show slight contrast in some sentences N5 〜で de Indicates where an action happens, means used, tool, cause, or material depending on context N5 〜と to Indicates company, quotation, natural condition, complete list, or direct connection between elements N5 〜の no Indicates possession, relation between nouns, nominal explanation, or turns a verb into a noun phrase N5 〜か ka Marks a question, alternative, or uncertainty, appears at the sentence end or between options