hit and miss
不確定的結果；可能成功或可能失敗的情況
口語·形容結果不可靠
英文釋義
something that is unpredictable or unreliable; often refers to a situation where success or accuracy is not guaranteed
例句
The Wi-Fi connection here is hit and miss; sometimes it works, sometimes it doesn't.
典故來源
源自射擊或投擲運動，擊中或未中完全隨機，比喻結果不確定。