The evil silent ones, like 'sword'

 As I have taught English, and as I have watched my daughter try to learn to read English, I have become aware again of the ridiculousness of evil - and nearly omnipresent - silent letters lurking surreptitiously in the undergrowth of English orthography. I say 'again' because I am quite sure that I was very aware of these entrapping oddities years ago as I tried to aquire the art form called reading.

 I do not say that these letters have no purpose for certainly with sufficient instruction the English spelling system can be learned. Indeed, in the case of vowels often the silent letters can give clear meaning. For instance, plumber could become plumer, but then it would be pronounced differently - so, it would need to be plummer. So, some silent letters can make sense, but there are the other, too...

  So, in solidarity with those seeking to decipher the sinister silent-letter riddles, I submit these repeat offenders and request the improvement of the English language through the abandoning of this ridiculousness.

half

know

clothes

gnat

built

sword

answer

castle

comb

hour

subtle

debt

bee

plumber

island

four

caught

vineyard

could

psychology

Often more usefully, these may also be silent:

any vowel 

doubled letters