i don't know what to do next.—it's easy.press the red botton in 2 minutes.这里问什么不用how

i don't know what to do next.—it's easy.press the red botton in 2 minutes.这里问什么不用how

what是疑问代词,在这里做do的逻辑宾语.how是副词不能作宾语,如用how ,就做状语,修饰do,那样句子就缺宾语,不完整.

缺了宾语，how to do it。