Gros:
* Size: Refers to physical size or volume.
* Implies: Thickness, heaviness, or bulkiness.
* Examples:
* Un gros livre (a thick book)
* Un gros chien (a large dog)
* Elle a un gros nez (She has a big nose)
Grand:
* Size: Refers to overall size or dimension.
* Implies: Height, length, or width. It often suggests a grandiose or impressive scale.
* Examples:
* Un grand château (a large castle)
* Une grande forêt (a large forest)
* Un grand homme (a tall man)
Here's a simple analogy:
* Imagine a big, heavy rock - you'd use "gros" to describe it.
* Imagine a tall, imposing skyscraper - you'd use "grand" to describe it.
Additional Notes:
* "Gros" can also be used figuratively to describe something as "large" in terms of quantity, intensity, or importance. For example, "un gros problème" (a big problem).
* "Grand" can also be used to describe something as "great" or "important," as in "un grand homme" (a great man).
In short, think of "gros" for physical thickness and "grand" for overall size and grandeur.