1. The coefficient of $x^{4}$ in the expansion of $(\sqrt{x}+1)^{4}(x-1)^{5}$ is $\qquad$
2, 1.45.
Notice that, in the expansion of $(\sqrt{x}+1)^{4}$, the coefficients of $x^{2}$ and $x$ are $\mathrm{C}_{4}^{4}$ and $\mathrm{C}_{4}^{2}$, respectively, and the constant term is $\mathrm{C}_{4}^{0}$.

Therefore, in the expansion of $(\sqrt{x}+1)^{4}(x-1)^{5}$, the coefficient of $x^{4}$ is
$$
\mathrm{C}_{4}^{4} \mathrm{C}_{5}^{2}(-1)^{3}+\mathrm{C}_{4}^{2} \mathrm{C}_{5}^{3}(-1)^{2}+\mathrm{C}_{4}^{0} \mathrm{C}_{5}^{4}(-1)^{1}=45
$$