I want to know the answer to the following question:
What type of deviations are there from the single phoneme to each grapheme general principle?
All the background I'm provided with is that "Although the Estonian orthography is generally guided by phonemic principles, with each grapheme corresponding to one phoneme, there are some historical and morphological deviations from this: for example preservation of the morpheme in declension of the word (writing b, g, d in places where p, k, t is pronounced) and in the use of 'i' and 'j'.[clarification needed]". Is that enough to answer the question?
Answer: yes