这种金鸡纳树的树皮是制造抗疟疾药物奎宁的重要原料。

The bark of the ___cinchona tree is a key source for making quinine to treat malaria.

金鸡纳树皮曾被广泛用于生产治疗疟疾的奎宁。

The ___cinchona bark was widely used to produce quinine for malaria treatment.