a)to be allowed to go into and leave a place whenever you want 来去自由,来去随便
The students can come and go as they please.
学生可以来去自由。
b)to keep starting and stopping 断断续续,时断时续
The pain comes and goes.
疼痛时断时续。
Examples from the Corpus
come and go• He wore a palegreen business shirt, and his shave was absolutely perfect, even as midafternoon came and went.• They each came and went as they pleased.• Only this can explain to me why he comes and goes, comes and goes.• A force that comes and goesdepending on your motion.• Certainly the variouscourtofficials who came and went didn't seem interested.• The girl was a good worker who came and went quietly about her business.• As the New Year came and went, so did millions of resolutions to turn over a healthierleaf.• Generations of policemen have come and gonewaiting for that mistake.