3. The sound [z] is spelled <ss> only rarely. In fact, the words above are just about all of the cases. Notice that the <ss> is always in the middle of the word.
4. The <zz> spelling of [z] is also rather rare. It is sometimes due to twinning, sometimes due to the VCC pattern, and it occurs between short vowels and <le>:
The words above in which <zz> is due to twinning are:
The words in which <zz> is between a short vowel and <le> are:
The words in which <zz> is in a VCC pattern are:
The words above in which [z] is spelled<s>are:
5. Some Other Spellings of [z]. In the Russian word czar, [z] is spelled <cz>. Another way of spelling this word is tsar, in which [z] is spelled <ts>. In the word asthma [z] is spelled <sth>. And the letter <x> at the beginning of words normally spells [z]: