Example of a space that's not a Haar space

Question

Definition 4. (Haar space)

Let B $\subset C(\Omega)$ be a finite dimensional subspace with basis $\left\{b_1,...,b_N\right\}$. Then B is a Haar space on $\Omega > \subseteq \mathbb{R}^d$ if $det(b_k(x_j)) \neq 0$ for any set of distinct points $x_1,...,x_N$ of $\Omega$.

This question might be super vague, but can anyone give me an example of a finite dimensional subspace that would not be a Haar Space? I'm working on a project dealing with multivariate Lagrange polynomial interpolation and need a "non-example"

Answer 1

http://www.math.iit.edu/~fass/603_ch1.pdf

Read theorem 1.2.2:

If $\Omega\subset \Bbb R^s$, $s\ge 2$ contains an interior point, then there exist no Haar spaces of continuous functions except for one-dimensional ones.