list of lists in Haskell - How can I seperate the first element of every list without map

for example: My list of lists in Haskell is:

[[1,2,3], [7,6,8], [0,3,4]]

I need all first element of ervery list in list.

How can I get the output [1,7,4] without "map"? I need a solution with pattern-matching, not this: list x = map head x