Hi
I want to ask your opinion , what more pretty ?
Chrome grille or Black grille ?
My lucerne is silver color

Hard to say. They both look good. The chrome, especially with silver, seems to blend together in an equally flashy fashion, where as the black looks more subdued, more formal.

Nither looks bad in my eyes, go with what you prefer.

The black grille looks better, it adds contrast to the front end. That'* a nice car. I usually add a little flavor to my cars but try to stay within the factory'* vision for the specific vehicle, nothing garish or gaudy. Different but still blending in. I had looked at purchasing the Lucerne in the past and the grille area needs "something" and I would have taken the headlights apart and tinted/painted some of that shiny stuff in the headlight reflectors to make those round bulbs standout, much like the 2001 Chevy Impala. Removed that amber sliver and put in an amber bulb.