I recently wrote a short series on pinyin, starting with this previous post, and today I want to just mention one of the common exceptions, and that's the silent letter i.
In the following words, the i sound is pretty much silent:
吃 (Chī) which means to eat
次 (Cì) which means a number of times or an order/sequence
日 (Rì) which means day
是 (Shì) which means is or yes
四 (Sì) which is the number four
字 (Zì) which means a word
只 (Zhǐ) which means only
Now there are other variants of the above sounds as well but they're the same pinyin letters. For example: 死 (Sǐ) which means death (and it's because it sounds a bit like the number four, that four is considered unlucky). Same for 子 (Zi) which relates to a child.
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