今天我们要学的词是vaccine。 Vaccine, 疫苗。"The Food and Drug Administration approved vaccines designed to protect against the H1N1 flu virus," 美国食品和药物管理局批准了甲型H1N1流感疫苗。

"The first doses of the vaccine will be available in just a few weeks," 第一批疫苗几周内就可以到位。"Clinical trials also show that the new vaccine protects with only one dose instead of two," 临床实验结果还显示，新疫苗一针就管用，不用两针。"The FDA's approval comes as the vaccine is still being tested in children and pregnant women." 与此同时，疫苗注射对儿童和孕妇是否安全目前还在实验阶段。好的，今天我们学习的词是vaccine...