sink or swim
US /sɪŋk ɔr swɪm/
UK /sɪŋk ɔr swɪm/

慣用句
1.
自力でやるか、さもなくば失敗するか, 成否は自分次第
to fail or succeed entirely by one's own efforts, without help from anyone else
例:
•
When he started his own business, it was a case of sink or swim.
彼が自分のビジネスを始めたとき、それは自力でやるか、さもなくば失敗するかだった。
•
The new employees were told they would have to sink or swim.
新入社員たちは自力でやるか、さもなくば失敗するかと言われた。
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