by accident

I entered this business purely by accident.(做这档子生意完全是出于偶然。)

We met together by accident.(我们偶然相会。)

Good feedback doesn't happen by accident.(好的反馈不是偶然发生的。)

Success is the result of devoting your time and energy to what you've set out to do, which doesn't happen by accident.(成功是投入时间和精力到你着手做的事情上的结果，它不会是偶然发生的。)

She was badly burnt by accident when she went out with her grandparents.(她在和爷爷奶奶一起出门时，发生意外，被严重烧伤了。)

None of this happened by accident.(所有发生的这一切都不仅仅是巧合。)

It was hard to know whether it happened by accident or by design.(很难知道这是偶然发生还是有意为之。)

The silver must have fallen into the dough by accident.(这些银子一定是意外掉进面团里了。)

He sliced (into) his fingers by accident when cutting vegetables.(他切菜时不小心切着了手指头。)

Most archaeological sites have been located by means of careful searching, while many others have been discovered by accident.(大多数的考古遗址都是通过仔细的搜寻定位到的，也有许多是偶然发现的。)