SQL: Basic Query

SQL: Basic Query

I have a more detailed description ready, but I thought I'd try the simple
one first.
X Y
7 F
7 F
7 E
7 F
8 F
8 F
I want to do something else based on figuring out if for a value (x) of X
there is a value of F in Y for all of the x's in the corresponding table.
This means 7 doesn't cut it, and 8 does. How do I code this using a
subquery? Do I use ALL? I wrote a query but it returns true whenever there
is one match instead of all.