injection drawing process

例句：

1. 1.The doctor administered an injection of painkillers to the patient.
   医生给病人注射了止痛药。
2. 2.The chemical was injected into the water supply to purify it.
   这种化学物质被注入供水系统中以净化它。
3. 3.The new drug was injected into the patient's bloodstream.
   新药物被注入患者的血液循环中。