そのうち・その内・其の内sonouchi

1. expression, adverbbefore very long; soon; someday; one of these days; sooner or later
   そのうち一緒いっしょに仕事しごとができるといいなと思おもっています。↗

   Hope we can work together soon.
2. expression, adverbof the previously mentioned; of that number; among them; among others

• SynonymやがてNeutralRefers to 'before long' or 'finally' (「やがて春が来る」), stressing natural arrival; can narrate the past. 「そのうち」 looks to the future with a vaguer time frame.
• SynonymまもなくNeutralMeans 'soon' or 'shortly' (「間もなく発車します」); the time is nearer than with 「そのうち」, and it is common in announcements.
• Synonym近々ちかぢかNeutralRefers to the near future (「近々伺います」); somewhat formal, with a clearer, closer time than 「そのうち」.
• SynonymほどなくWrittenWritten style, meaning 'soon after' (「ほどなく到着した」); mostly narrates the past, while 「そのうち」 speaks of the future.
• Synonym今にいまにCasualColloquial, meaning 'one of these days' (「今に見ていろ」), often with a warning or prophecy; 「そのうち」 is more neutral in tone.
• Synonym遠からずとおからずWrittenWritten style for 'in the near future' (「遠からず実現する」); often used in predictions and more solemn than 「そのうち」.
• Synonym近くちかくNeutralAs an adverb, 'in the near future' (「近く発表される」), common in news reports; it also means 'nearby' or 'nearly', senses 「そのうち」 lacks.
• SynonymそろそろCasualColloquial, 'it's about time' (「そろそろ帰ろう」); stresses that the moment has come, more imminent than 「そのうち」.
• SynonymいくばくもなくWrittenWritten style for 'not long after' (「いくばくもなく亡くなった」); mainly narrative. In everyday speech say 「間もなく」.
• Synonym近いうちにちかいうちにNeutralMeans 'soon' or 'in the near future' (「近いうちに会おう」); the time frame is closer and more concrete than 「そのうち」.
• Synonym不日ふじつWrittenWritten style for 'within days', seen in official documents and letters; in daily speech say 「近いうちに」.
• SynonymもうすぐCasualColloquial, 'only a little while to go' (「もうすぐ夏休みだ」); the event is close at hand and more definite than with 「そのうち」.
• Synonym日ならずひならずWrittenWritten style for 'within a few days'; rare. In everyday speech use 「間もなく」 or 「近いうちに」.
• RelatedすぐNeutralMeans 'right away' (「すぐ行く」), the nearest time of all; 「そのうち」 leaves the timing open.
• Related今にもいまにもNeutralMeans 'on the verge of' (「今にも雨が降りそうだ」), often with 「そう」, for things about to happen any second; 「そのうち」 only says 'before long', without that sense of urgency.
• Related後ほどのちほどFormalPolite, formal 'later on' (「後ほどご連絡します」), typical of business and hospitality; usually a short interval, while 「そのうち」 can reach further into the future.
• Related追っておってWrittenWritten style for 'later, separately' (「追って連絡する」), common in notices; it can also mark a postscript, a use 「そのうち」 lacks.
• Related追っ付けおっつけCasualColloquial, 'before long' (「おっつけ来るだろう」) with an old-fashioned flavor; people now say 「もうすぐ」.

Use 「そのうち」 for an indefinite future time or 'one of these days'. For 'right away' choose 「すぐ」; for something just a short while off, 「もうすぐ」; for plans in the near future 「近いうちに」 or 「近々」; for a polite 'later' in business 「後ほど」; for something on the verge of happening 「今にも」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 実現じつげんするまでにあまり時間じかんを要ようさないさま。近ちかいうち。