Y = sp { [1,0,4,3]^T, [0,1,0,-1]^T, [2,-1,1,0]^T, [0,1,4,3]^T}

Question:
Find a basis for the subspace Y by eliminating from the spanning
set any vector that can be expressed as a linear combination of its
predecessors. State the dimension of Y
.

I'm roughly know what I'm doing here, but I can't seem to eliminate any vectors at all. Any help?