冬眠的羽毛
简单直译:He carelessly lost his cellphone.如果强调不小心:It was careless of him to lose his cellphone.如果强调物件:His cellphone was lost by accident.(个人觉得用被动语态较好,因为被动语态比较强调事件本身,而非人。不过还要参照你的上下文,意思表达得恰当就可以了。)
贪嘴森淼
Description: My boyfriend inadvertently lost mobile phones, tomorrow is his 22-year-old birthday, I bought a new phone as a birthday gift trailers were brought, because I want to contingencies elsewhere, can not be given to him face to face, That is Samsung's mobile phones and it has cameras.