keep step with (与…)齐步前进,(与…)步调一致,跟上
keep pace with 并驾齐驱,保持同步
keep step with主要意思为与谁同步,一起.而keep pace with则有一种相互竞争的意思,谁也不干落后,一般情况下可通用,但在表特定意思下就得分开用!