You would say;
Great-grandfather = Hen Daid
Great-grandmother = Hen Nain
A family backround is what your parens grandparents greatgrandparents and so forth did like what they did to support the family or in other words what their job was.
If the First Cousin of your parent has a child, that child is your Second Cousin. You have one or more Greatgrandparents in common. That is the deifnition of a Second Cousin.
I know for a fact that people in Wales are called Welsh.
"You are Welsh" = Rwyt ti'n Gymreig
Draig Gymreig
'gyda dy Gymraeg di' is 'with your Welsh'
The Welsh word for "Welsh" is Cymraeg :)
No in Welsh is dim.
ymchwil Gymreig = Welsh research ymchwil Gymraeg = Welsh language research
No Welsh equivalent.
The welsh for slow is ARAF
'Flicker' is not a Welsh word and has no meaning in Welsh.