English : The letter Q has the same hard sound as the letter K or C yet we don't see words such as kween or cween. Why not?
When we borrowed words from Latin and French we brought over their spelling, and they use the Q. Not that it's logical in French or Latin either; it could virtually always be replaced with a C in those languages. Eventually we started using the Q to spell a few native Anglo-Saxon words like quick and queen.
Also, why do C's sound like an S at times?
More Latin. In Classical Latin, C was always pronounced K. But there's a powerful force called
palatalization that affects the phonetic development of many languages, if not most or even all of them.
When we let our tongue relax and then slowly lift it, it touches the roof of our mouth on the palate. At the opposite extreme are linguodental consants like English TH and velar or uvular sounds like Russian KH, which require using muscles to reshape the tongue and move it forward or backward.
So, over time a T or a D can slip backwards and become something like S, SH, ZH, or the more complicated palatalized Ty and Dy sounds of Russian. And a K or G can slip forwards into the same position.
In Vulgar Latin, when a K or G came before a vowel like E or I which moves the tongue upward, the K or G slid forward. In Italian and Romanian they became CH and J, respectively. In French and Portuguese they became S and ZH. (We won't talk about the Arabic influence in Spanish that broke the rule and turned them into the odd TH and KH phonemes.)
Even in American English (but not British) we palatalize the T in "mature" and "woncha go with me?" and the D in "educate" and "didja like that movie?" Chinese is full of palatalized consonants, which is why "Peking" is really "Bei-Jing." (BTW that's an English J, people who say Bei-zhing need a good map because they must think it's in France.) Japanese has a huge series of palatalized consonants. There are no such syllables as TI, SI, DI or ZI in Japanese, only CHI, SHI, JI and ZHI.
Anyway, English assimilated thousand of French words after the Norman Invasion in 1066, so the "soft C" became part of our spelling. You'll probably find that most of the words with soft C are of French origin (or Latin via French, or Greek via Latin), although there are exceptions like "ice."
Do we have more letters in the alphabet than we need?
Quite the contrary, we don't have nearly enough. English has more phonemes (individual units of sound) than Russian, and the Russian alphabet has 33 letters (I think, depending on how you count).
We have to use two letters to spell SH, CH and TH, and even then we don't know if it's the CH in church or Mach One; the TH in bath or bathe. We don't have any way to spell ZH, we just hope everybody can figure out the S in vision and pleasure.
We have only five letters for vowels, six if you count Y. Yet we have eleven vowel phonemes (again, depending on how you count). A has to represent the sounds in far, plate and cat. E is for set and complete. U is for up, flute and put.
We could reclaim Q and C and use them to transcribe two other phonemes, but we'd still need about ten more letters before we had a truly phonetic alphabet.
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