根据英语翻译下面短语的意思并完成句子。
1. by chance _____
2. by accident _____
3. by mistake _____
4. by luck_____
5. by design _____
6. by good fortune_____
7. by necessity_____
8. I met an old friend of mine _____ in the street.
我在街上偶然碰到了老朋友.
9. — How did you find your lost bike?
你如何找到的你丢失的自行车?
— _____.
凑巧找到的.
10. I had no trouble passing on the driving test in the end ___.
由于运气好最后我通过了驾照考试.
11. He has finished his task ahead of time______.
由于进行了周密的筹划,他提前完成了任务.
12. The war will break out between the United Sates and Iran_____ in time.
伊美之间迟早会不可避免地爆发战争.