構造的には「He's afraid his wife will find out he is 〇〇」の〇〇に問題の行為を入れればちゃんとした英文になります。
例えば、浮気をしていることがバレるのが怖いなら「He's afraid his wife will find out he is cheating on her」になります。
動詞だけでなく、形容詞も使えます。
例文:
- He's afraid his wife will find out he is gay
1) He is scared that his wife will find out about "________"
2) He is scared that his wife will catch him "________"
find out about 〇〇~ 〇〇についてバレる
catch ~ (つかまる)ニュアンス的にバレるという意味
例:
1) He is scared that his wife will find out about his gambling addiction
2) He is scared that his wife will catch him cheating on somebody else
1) gambling addiction= ギャンブル中毒; 彼は妻にギャンプル中毒のことがバレるのが怖い
2) cheating 浮気; 彼は妻に他の人と浮気したのがバレるのが怖い