First of all, do you know the meaning of “tan” and “tanto”? “Tan” can be translated as “so” (adverb) and “tanto” can be translated as “so much”. Apart from that, “tan” is an adverb in Spanish, for that reason this word never changes. However, it doesn’t happen the same to “tanto” because it is an adjective. For that reason, the word will change according to the noun which goes with it.
Let’s do an easy translation:
So tired > tan cansado
So upset > tan disgustado-a / molesto-a / enfadado-a
Now, let’s try a translation using “so much”:
So much muscular tension > tanta tensión muscular
So much money > tanto dinero
So many shops > tantas tiendas
So many books > tantos libros
Have you seen the changes of “tanto”? When it’s followed by a feminine noun (tension means tensión and it’s a feminine noun), we translate “so much” as “tanta”. When it’s followed by a masculine noun (dinero), we translate “so much” as “tanto”. On the other hand, when we talk about plural, we use “so many” in English. “So many” is “tantos” when the noun is masculine and plural (libros) and “tantas” when the noun is feminine and plural (tiendas).
I hope all is clear! If you have doubts, don’t hesitate to ask me in the comments below! Apart from that, you always can contact me > belriesco@outlook.com .
Don’t forget to share this post with your friends if you consider it useful! I really appreciate it! I hope to see you in the next post. 😊
Cheers!
Letras en Español – Ms. Riesco Almeida ©

REFERENCES
Cambridge online dictionary: Cambridge Free English Dictionary and Thesaurus