it will be hard for us to get up in the morning if we --- to bed too latea\ go b\ wentc\ will god\ have gone 请说明理由好吗?

问题描述:

it will be hard for us to get up in the morning if we --- to bed too late
a\ go
b\ went
c\ will go
d\ have gone
请说明理由好吗?

A
主将从现
类似的还有until,unless等

选A.
这是一个条件状语从句,所以根据主将从现的规则,从句要用一般现在时,即go。

if的条件状语从句,主句用将来时,从句用一般时态,所以选A