Note that this sentence is the equivalent of the English phrase "I have (a lot of) thirst."
Because "sed" (thirst) is a feminine noun, you need to use feminive adjectives (mucha, a lot of) to match.
wrong the languages don't translate word by word. Nobody says I have thirst.
Yes, "I am (very) thirsty" is a much more natural translation. I'm giving the literal word-for-word translation to show that "mucha" is an adjective and must be modified to match the noun.
Do you need to say "mucha" because "sed" is a noun? Thus, you cannot say "muy sed", correct? How would you say "I am thirsty a lot"? Tengo sed a menudo?
Tengo sed does make sense if it's used in the context of - I have a thirst for knowledge.
I find the pronunciation very difficult both on lap top and iPad - I listened over and over and my wife and I agreed the last word sounded like serra - made no sense, especially since sed is pronounced se by our native Spanish speaking friend!
it's the equivalent of I am thirsty. Not once in my life have I ever heard, I have thirst
There is a difference between a translation and a literal translation. No, we do not say: "I have thirst" in English, but literal translations are often helpful to identify the use of idiomatic expressions with the verb tener and remember the rules for future use.