drop by 随便来,随便来玩,随便走访,非正式访问
例句：
Drop by whenever you have time.
如果有空随便来
Drop by whenever you feel like it.
随时即兴就来我这儿坐坐
I'll drop by on my way home if I have time
有空的话回家途中我会顺便来看你
I have to drop by the bank to get some money
我得到银行去取一下钱
She and Mary are dropping by later.
她和玛丽一会儿要来坐坐