NASA successfully tested the largest most powerful rocket booster ever-made.

美国航空航天局成功试射了史上最强大的火箭加速器。

Moderna announced on Monday that it is testing an additional booster of its vaccine against the new variants.

周一，莫德纳宣布其正在测试一款强化注射疫苗来应对病毒变体。

Both Moderna and Pfizer have since announced they are testing a booster of the approved vaccines against the new variants.

莫德纳和辉瑞宣布其正在测试一种基于已审批通过疫苗的强化注射疫苗，用以对抗病毒变体。

Fischman: And this summer, vaccine makers and the FDA will be testing these new boosters to make sure they are just as successful at keeping up.

Fischman：今年夏天，疫苗制造商和 FDA 将测试这些新的助推器，以确保它们同样成功地跟上步伐。