chance on 或 chance upon

To find or meet accidentally; happen upon

偶然找到，偶然遇到；偶然碰到

While in Paris we chanced on two old friends.

在巴黎我們偶然碰到兩位老朋友

as chance would have it

as it happened

湊巧，偏偏

by any chance

possibly (used in tentative enquiries or suggestions)

萬一，也許（用于試探性的詢問或提議）

were you looking for me by any chance?.

你有可能是在找我嗎？。

chance one's arm (或 luck)

(Brit. informal)undertake something although it may be dangerous or unsuccessful

(英，非正式)冒險一試

chance would be a fine thing

(informal)expressing a speaker's belief that something is desirable but the opportunity is unlikely to arise

(非正式)成功固然好，只惜良機少

no chance

(informal)there is no possibility of that

(非正式)絕無可能

on the (off) chance

just in case

萬一

stand a chance

[usu. with negative]have a prospect of success or survival

有（成功或生存的）希望

his rivals don't stand a chance.

他的對手毫無成功的希望。

take a chance (或 chances)

behave in a way that leaves one vulnerable to danger or failure

冒險

take one's chance

do something risky with the hope of success

（為了成功而）冒險，碰運氣

by chance

Without plan; accidentally

意外地；偶然地

They met by chance on a plane.

他們在飛機上不期而遇

Possibly; perchance

或許；可能

Is he, by chance, her brother?

他可能是她哥哥嗎?

on the off chance

In the slight hope or possibility.

萬一發生：抱著微小的希望或可能性