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"That much" is an adverb which is often translated as "tanto", and "so many" is a phrase which is often translated as "tantos". Learn more about the difference between "that much" and "so many" below.
so many()
A phrase is a group of words commonly used together (e.g., once upon a time).
a. tantos
Look at all these flavors! There are so many it's hard for me to just pick one.¡Mira todos estos sabores! Hay tantos que no puedo escoger solo uno.
