keep up

保持 继续 维持 跟上(时代)

例句与用法：

The house is becoming too expensive for them to keep up.

他们的房子维修费用贵得越来越修不起了。

The high cost of raw materials is keeping prices up.

原料费用昂贵使得产品价格居高不下。

The enemy kept up their bombardment day and night.

敌军一直日夜不停地狂轰滥炸。

详细释义：

1. (使)不停止

Rain kept up all day.

雨下了一整天。

2. 保持

He kept up a correspondence with Tom.

他和汤姆保持通信联系。