Final answer:
The rule pronouncing the Spanish letter is based on sounds in words.
The pronunciation of the Spanish letter 's' as [z] or [s] depends on the sounds before and after it.
Step-by-step explanation:
When the letter 's' is between two vowels, it is typically pronounced as [z]. For example, in the word 'mismo' (same), the 's' is pronounced as [z] because it is between the vowels 'i' and 'o'. Another example is the word 'isla' (island), where the 's' is pronounced as [z] because it is between the vowels 'i' and 'a'.
However, when the letter 's' is at the beginning of a word or comes before a consonant, it is pronounced as [s]. For example, in the word 'este' (this), the 's' is pronounced as [s] because it is at the beginning of the word. Similarly, in the word 'pescado' (fish), the 's' is pronounced as [s] because it is followed by the consonant 'c'.
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