Learn English – Long vs. short vowels in English words of Latin origin

The trailing i on most masculine nominative plurals in Latin is usually a “long e” /iː/, as has already been stated, like ee in levee or tree. Latin pueri (the boys) would be /pu.eri/ poo-air-ee.

A trailing ae like that found on most feminine nominative plurals is a diphthong which sounds a lot like a “long i” (/aɪ/, [äɪ̯]), but, as it is a diphthong, is more of a switch in sound starting with a “short a” /ɑ/ and ending with a “long e” /iː/, similar to the pronunciation of aye or eye /aɪ/. Thus, Latin puellae (the girls) would be poo-ell-aye /puɛlːaɪ/.

I’s at the beginning of words are pronounced like the y /j/ in yet /jɛt/ or yellow /ˈjɛloʊ/, and C’s were usually hard /k/. So, Julius Caesar (which would have been written ‹Iulius Caesar›, as they didn’t have J’s), would have been pronounced something like Yul-ee-us Kai-sar /ˈjuː.li.ʊs ˈkae̯.sar/, the pronunciation of which is where Germans get the word Kaiser, Russians get Czar, and Arabs get Qaysar, amongst a dozen other languages that have words rooted in the word Caesar.

Unfortunately, there is no good rule - children struggle with this when learning to write. There are a few rules of thumb that hold in most cases, though:

• Diphthongs (ou, ie, ei, eu, ...) are long (accOUnt), unless they're unstressed and turn into a schwa (succOUr)
• Single vowels (a, e, i, o, u) are short before double consonants (AttAck)
• Single vowels are long if they are followed by a single consonant and then an 'e', all in the same syllable (sAve, mOle), and in -ing forms of such verbs (sAve -> sAving)
• Single vowels are short if they are followed by a single consonant in the same or next syllable, unless the above applies (cAt, At-lAs, nO-mEn-clA-ture)
• And loads of exceptions to all of these rules, and they vary across dialects and idiolects. The consonants 'r', 'w' and 'y' do funny things to vowels, too.

These might help a little:

http://en.wikipedia.org/wiki/Vowel_length#Short_and_long_vowels_in_English

http://improvingenglishspelling.blogspot.co.uk/2010/06/long-and-short-vowels.html