艺术家使用凹版腐蚀技法在铜版上创作出细腻的渐变色调。

The artist used ___aquatint to create subtle tonal gradations on the copper plate.

她在艺术展上购买了一幅展示各种版画技法的凹版蚀刻画。

She bought an ___aquatint at the art exhibition that showcased various printmaking techniques.