since自从,从字面来说就是:自从过去的某个时间点到现在怎样了. 如果since后的时间状语从句的谓语是个短暂性动词,就很好理解.如: It's / has been 4 years since i met him last time.自从我上次看到他到现在有四年了. 但是,如果since后的时间状语从句的谓语是个待续性动词,如你的题,这个时间就要从这个动作结束时算起.所以,你的题意为:自从我病好后,我就没上街购过物.又如: It's / has been 4 years since i was a teacher.我不当老师有四年了. PS:这类题,在单项选择题中出现的机会较少,因为现在的考题基本上都是语境题,不过在阅读理解题中,针对这样的一句话来提问(What does the underlined sentence mean?)是有可能的.