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irresponsible; perfunctory; careless
lukewarm; half-baked; halfhearted; vague
(already) enough
considerably; quite; rather; pretty
いい加減にしないと信用を失ってしまう。
If you don't stop being irresponsible, you'll lose trust.
いい加減な態度では成功できないだろう。
You probably can't succeed with a half-hearted attitude.
もういい加減に決めないと間に合わない。
We need to decide already or we won't make it in time.