The letters can be used to spell the 5 letter word lemon. They also spell the word melon.
You are asking us to construct a seven letter word, using twelve letters. This does not seem to be mathematically possible.
Here are the possible options:greaveraggeeregavereggae
There are no eight letter words using these letters.The longest possible words have seven letters and include:CatfallChapletFlatcapHellcatHematalPalmatePatellaPlacate
There are no possible 10-letter words, there are these 9-letter words though:antikingsknightingthinkingsvanishing
it is 336
3,124,550 possible combinations
120
150
The answer would be 210
-3
-5
Breeder is a 7 letter words using only those letters