For each alternating bilinear form $ f$ over a finite dimensional vector space $ V$ , there exists a basis of $ V$ such that the matrix of $ f$ is given by $ $ \begin{pmatrix} 0&1& & & & & & & \ -1&0& & & & & & & \ & &\ddots & & & & & \ & & &0&1& & & \ & & & -1& 0& & & \ & & & & &0& & \ & & & & & & \ddots& \ &&&&&&&0\end{pmatrix}.$ $ (all other elements are zeroes!)

My question:

I understand where the blocks $ \begin{pmatrix} 0&1\-1&0\end{pmatrix}$ come from, but the sequence of $ 0$ ‘s on the diagonal after the last block confuses me. Where does it come from?