SHHH, silent vowels.

[jinksys]

Are there specific rules that dictate what sounds are silent in words?
for example はじめまして, the shite is reduced to SH-te.
how do I know if a ます ending is MAS or MASU ?

[clay]

I am not sure about a rule, but another example is suki which is often pronounced 'ski' usually.

[Spaztick]

There isn't anything specific, but usually just learning which are silent by listening is the best way to learn.

(Also, sukoshi is pronounced "skoshi").

[jiro]

ya i was wondering that too. cuz i learn words in romaji, and then when i try to say them, i dont know if i am pronouncing them right or not.

[fuqiang8]

Got this info from a book.

The vowel u is sometimes not pronounced.
The most common are: between k and s (eg gakusei, 'student', sounds like gaksei.)It's also dropped in the verb endings -desu and -masu (ii desu, 'its's good', sounds like ii des).

Hope this helps.

[TokyoRoze]

Ty that helped me

[Sunny Pig]

The only time I know that the vowels are silent are actually 「です」and 「ます」.

The reason you hear missing vowels is actually due to the fact that the "u" is not properly pronounced during fast speech, which is very common.

For example, try repeatedly saying 「がくせい」really really fast.
You will realise that you will begin to slur and you will begin to pronounce it like "gak-sei". Many other words would also have the same effect when spoken quickly.

Actually, if you want to sound more polite, you can pronounce the "u" in 「です」. You don't have to emphasize on the "u", just pronounce it lightly.