fall behind等于哪些词

fall behind等于哪些词 fall behind fall behind是什么意思 fall off fall over fall behind fall down 区别的 fall behind in 和be behind in 的区别~ left behind与fall behind有什么区别 He tried（ ）{not fall} behind others用所给词的适当形式填空. 用fall behind 造个句子~ He tried _____(not fall) behind others. fall behind 用汉语翻译是? fall behind with sb 和 fall behind with sth 的意思分别是什么? 1.He's working hard ____ he should fall behind.