•You chose exactly the same wallpaper as us - what a coincidence!你选的壁纸跟我们的一模一样——真巧！

•Is it just a coincidence that the wife of the man who ran the competition won first prize?赢得冠军的人是竞赛组织者的老婆，这难道只是巧合吗？

•a series of strange/amazing coincidences一连串奇怪／令人惊讶的巧合

•Just by coincidence, I met my old school-mate again fifty years later.纯粹是碰巧了，我在50年后又遇到了我的老同学。

•[+ that] It was pure/sheer coincidence that I remembered his phone number.我记住他的电话号码纯属偶然。

•By some strange coincidence, he was passing the house just when it happened.事情发生时他碰巧路过这所房子。