ahead
同义词：
forward | before | in front | in advance | onward | on | along | forth | first | advance | in | front | leading | winning | forwards | in the future | to come | early | prematurely | fast | gaining | or | in the lead | beforehand | out front | onwards | forrader |
反义词：
词义辨析：
同义:
ad.在前; 领先
forward
before
in front
in advance
同义参见:
forward or forwards
forth
first
along
onward
on
反义:
ad.在前; 向前; 领先
behind
反义参见:
astern
backward
aback