Thank you so much, it works.
one more question is how can I match the grid layout placement?
I mean please check the image: https://imgur.com/nJsNZTQ
you can see the continue reading button placement isn’t the same for the grids. the alignment is not matching, I want to make the boxes position to the same for every grid. I set the excerpt word count to 30 words. but the read more button position aren’t the same for every grids.