yī / shēng / tōng / guò / xiǎn / wēi / jìng / guān / chá / fèi / pào / de / jié / gòu / pàn / duàn / bìng / qíng医生通过显微镜观察肺泡的结构,判断病情。The doctor examined the structure of the alveoli under a microscope to determine the condition.