passive immunization

• 被动免疫

passive immunization的用法和样例：

例句

1. This is called passive immunisation.
   这叫作被动免疫。
2. Although passive immunization now seems to hold the most promise, active immunization is not out of the running.
   虽然目前看来是被动免疫最具潜力，但是主动免疫也不见得就此退出赛局。