駅で切符を買えないおじさんがいた、と言いたい時はThere was a middle aged man who couldn't buy a ticketでしょうか？There wasは必須ですか？（A man couldn't ...だけでは〇〇な人がいたんだっていうニュアンスでなない？）I found又はI sawを使わなくてもOK？personやguyを使った方が適切でしょうか？
- "There was a man who 〇〇"
"there was ~" 「〜がいた」、"there is ~" 「〜がいる」
"a man" 「人」・「男」"person" や "guy" も使えます。
"a man who ~" 「〜な人」
"There was a middle aged man at the station who couldn't buy a ticket."
「駅で切符を買えないおじさんがいた」
"There was ~" は必要です、代わりに "I saw ~" も使えます。 今回の場合 "I found" はおかしな言い方ので使いません。
"at the station" 「駅で」使っても使わなくても大丈夫です。切符を買えないのことで場所が分かりので。そしてもし使ったら "There was" を使わなくて大丈夫になります。
There was a middle aged man at the train station who was having trouble buying his ticket.
I saw a guy in his 50's at the train station who didn't know how to buy a train ticket.
この場合は、There was や I saw などを使うと良いでしょう。
ーThere was a middle aged man at the train station who was having trouble buying his ticket.
「駅に切符を買えない中年の男性がいた」
to have trouble buying his ticket で「切符を買うのに苦労する」
ーI saw a guy in his 50's at the train station who didn't know how to buy a train ticket.
「駅で切符を買えない５０代のおじさんを見かけた」
how to buy a train ticket で「切符の買い方・切符を買う方法」
ご参考まで！
オーストラリア 
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