  Let $(X, T)$ be a weakly mixing minimal system, $p_1, \cdots, p_d$ be
integer-valued generalized polynomials and $(p_1,p_2,\cdots,p_d)$ be
non-degenerate. Then there exists a residual subset $X_0$ of $X$ such that for
all $x\in X_0$ $$\{ (T^{p_1(n)}x, \cdots, T^{p_d(n)}x): n\in \mathbb{Z}\}$$ is
dense in $X^d$.
