Correct

磨洗

/ mó xǐ / 
Strokes

Example

As a Verb

corrode; erode; wear away

1
Zhèxiē
这些
bìhuà
壁画
jīngshòu
经受
le
了
shíjiān
时间
de
的
móxǐ
磨洗
  
。

These frescoes had been worn away over the years.