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Using Hiragana, how would you write a word/transcribe a sound which ends in a consonant? Such as 'kon'. Relevant to this, I don't understand why 'hajimemashite' doesn't pronounce the 'shi' in the word, and why in the phrase 'watashi wa ______ desu' the 'su' isn't pronounced, and in 'watashi wa _______ to iimasu', again, the 'su' isn't pronounced. Is there a grammatical reason for this?