So how in the world could GHOTI be pronounced FISH in English?
Well let's take a look at GH. In English this sound used to be represented as X, coming from Gaelic. For example, in all these words, the GH sound is an F sound:
The second sound, O, in English, is at times pronounced as an I. This is the only example I can think of in English where an O is pronounced as an I.
Now let's take a look at TI. This sound is like SH in English, and there are many examples of this because English has a ton of words ending in TION:
So to summarize:
GH (F) O (I) TI (SH)
Now we can see that English is NOT a phonetic language (a language in which letters represent the same sounds every time.)