英语语法分析

Chloroquine and antifolate drugs such as the sulphadoxine-pyrimethamine combination are safe and are still used in some regions because of their low cost.

Chloroquine和抗叶酸药物如sulphadoxine - pyrimethamine组合药物是安全的，而且仍在某些区域被使用，因为它们的价钱低。