是祈使句,不用going是因?yàn)楹竺孢€有and it will..,以Go to bed early and it will keep you active during the day為例,如果用going,就是Going to bed early will keep you active during the day....是復(fù)合句和簡(jiǎn)單句的區(qū)別么。是不是說(shuō)，Go to bed early已經(jīng)是個(gè)完整的句子了，然后and it will keep you active during the day是什么？Going to bed early will keep you active during the day.是動(dòng)名詞作主語(yǔ)的簡(jiǎn)單句么？恩，Go to bed early 已經(jīng)是一個(gè)完整的句子了，無(wú)需用 ing，后面的 it willkeep you active during the day 也是一個(gè)完整的句子，中間用and連接的，即用and連接了兩個(gè)句子，it代指go to bed early.Going to bed early will keep you active during the day是動(dòng)名詞做主語(yǔ)的句子。