In the 研究社 dictionary, under 持つ heading, example sentences for some sub-entries use kana only. How can I tell when kana is more appropriate in my own writing?
Here's an example of the sub-entry where no example uses kanji. I'm guessing kanji in this meaning would be unusual.
12 〔長持ちする〕 wear; last long; keep; keep [remain] good; hold (up); endure; be durable; 〔死なずにいる〕 live (out); survive. [⇒もたせる２ 3] よく[長く]もつ stand; last [keep] long; wear [stand up] well; be durable; give excellent wear
・今夜いっぱいもつ 〔食べ物が〕 keep overnight [through the night]; 〔病人が〕 live through [out] the night
・(品物が)一生もつ last (out) one's lifetime.
その建物はまだあと 100 年はもつだろう. The building will stand another century.
・この上着は 3 年もった. This coat has lasted me three years.
・食糧はもうひと月もつ. There is enough food to go another month. ｜ Our food will last one more month.
・この好天気はそう長くはもたない. This beautiful weather won't hold much longer.
・小遣いが月末までもちそうにない. I'll run out of pocket money before the end of the month.
・この安普請では 10 年ともつまい. This cheaply built house won't last ten years.
・そんな粗末な食事では体がもたないだろう. You cannot keep yourself in good health [Your health won't hold up] on such a poor diet.
・その病人はひと月ともたないだろう. The sick woman does not have a month to live.
・病人は今年いっぱいもたないかもしれない. The patient may not last the year out.