一有机会

• on the first opportunity
• on the first occasion
• at the earliest opportunity
• at the first opportunity

例句

1. 别再犹豫了，一有机会就抓住它！
   Don't hesitate; seize the first opportunity that comes along!
2. 我一有机会便将尊函转交给她。
   I'll forward your letter to him on the first occasion.
3. 一有机会，小偷便会抢走你的最后一个铜板。
   The thieves will snatch your last bob if you give them half a chance.