Why can ch sound like ch, s and k?

Can't it just pick one?

The pronunciation of the "ch" sound in English can indeed be somewhat perplexing due to its multiple variants, such as in "chocolate" (ch), "machine" (sh), and "ache" (k). This diversity is a result of the historical development and borrowing of words from various languages.

• Latin and French Influence (ch as sh)
  In words like "machine," which have Latin or French origins, the "ch" is pronounced like "sh." This is due to the influence of the French language, where "ch" often represents the "sh" sound.

• Native Germanic Words (ch as k)
  In words with Germanic roots, like "ache," the "ch" is pronounced as "k." This is a reflection of the original pronunciation in Old English.

• Greek Influence (ch as k)
  Some words, especially those borrowed from Greek, retain the "k" sound for "ch." For example, in "chorus," the "ch" is pronounced as "k."

• Common examples: Chat, Check
  This is the most common pronunciation of "ch" and is similar to the "ch" sound in "church." It occurs when "ch" is followed by most consonants and some vowels.

In the category of silent "ch," one notable example is the word "yacht." The silent "ch" in "yacht" can be traced back to its Middle Dutch precursor, "jacht," which means “hunt” showcasing the influence of linguistic evolution on pronunciation in borrowed words.