(1)進行時制で、過去に動作が進行中だったことを示すときに使われる
(2)a progressive tense used to describe on-going action in the past; "`I had been running' is an example of the past progressive"
さらに詳しく
(1)肺の鬱血を軽減する薬
(2)a drug that decreases pulmonary congestion
