什麼是front and back ?

母語人士的回答
Rebecca
“ Know something front and back ”一詞是指通過學習Know something front and back在專家水平上擁有完善的知識。這個成語來自於表達對know something backwards and forwards的know something backwards and forwards 。這種表述比front and back更為普遍。例子: She's read the book so many times, she knows it backwards and forwards. (她讀過很多本書,所以她非常了解這本書。)例子: He knows cars front and back. (他很了解汽車。)