Days of the Week

Time

The vowels I & U are normally devoiced when they occur between voiceless consonants. SO, when 一(ich[i]), 六(rok[u]), 八(hach[i]) are combined with 分(fun) they are devoiced. This process creates a succession of voiceless consonants (ichi-fun, rok-fun, hach-fun.) In Japanese, when two voiceless consonants are next to each other some modification may occur. In this instance, the ‘f’ in 分 becomes a long ‘p’, resulting in いっぴん、はぷん、ろっぷん。Note that 三分 (さんふん）and 何分（なんぷん）are exceptions to this.

10 is usually pronounced じゅう but when followed by a word that begins with a voiceless consonant it is pronounced as じっ。

However, most Japanese people nowadays pronounce 10 oclock as 第十課　（だいじゅっか）