I have a question about the timing,If i use a monster with eff that activates when he is sent to the grave, sometimes their activates and sometimes no.Example: Using Gem-knight aquamarine to a fusion, she can use her eff. Using gusto gulldo to a synchro, he cant use his eff. Thats some difference about fusion material and synch material, or its another thing? (sorry about the worst english haha[:wall:] [:wall:] [:wall:] )

well there is a big difference with :
When ... you can...
and
If ... you can ...

Try to read this :
http://yugioh.wikia.com/wiki/Missing_the_timing 

its hard for me to explain it. =_=

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