Why not take different routes to run away =Shall we take different routes to run away?
同义句主要是考察Why not吧!它后面接动词原形,只有shaa we了,其他诸如how bout,what about+Ving形式,还有why don't you呀,what do you think of后面也接动词原形,不过这儿要求只填两个单词,所以我觉得就填shall we了.