what does v/cv and vc/v mean

It has to do with the division of a word's syllables and where the long and short vowels are in that word.

Examples:

haven = ha / ven = v/cv
The first vowel is long (sounds the way you pronounce it when you say the alphabet); the second syllable starts with a consonant (thus the "c") and has a short vowel.

Read more here:
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