落后于时代

fall behind the times

我们是同时出发的，但是他走得慢，稍微落后了一点。

We set off at the same time but he progressed slowly and lagged behind.

落后于进度表

lag behind on schedule

比原计划落后了两个月

fall two months behind on the original plan

落后的技术

outdated technology

文化落后

be backward culturally

经济落后

be underdeveloped economically

经济落后的国家

economically underdeveloped countries

技术落后

be underdeveloped technically

思想落后

have thoughts far behind the times

不甘心于落后

be unwilling to lag behind

摆脱落后的地位

cast off the stigma of being underdeveloped