Lucy with her mother often ___ to the zoo.
问题描述：
Lucy with her mother often ___ to the zoo.
答
goes因为Lucy with her mother属于单数，
而如果是Lucy and her mother就是复数，
那才用go
答
goes，主语是Lucy,单数形式，withe her mother是表示附加条件的副词词组。
如果是lucy and her mother那就应该是复数了
答
goes
“with her mother”是插入语,可以把这句话看做“Lucy often goes to the zoo with her mother.”所以主语其实是with前面的人,如果前面是两个人以上就用复数形式.但with和and不一样,如果是“Lucy and her mother often ___ to the zoo.”就要用go了.
还有一种either...or\neither...nor什么的就是就近原则,单复数依据临近助词进的主语,比如：Either students or teacher likes the party.Neither Anne nor her parents do the wash.
答
Lucy with her mother often goes to the zoo.
你看那用的是with而不是and就说明主语是lucy
就是第三人称单数咯
其实 正常应用中 很少出现这个句子的 挺别扭的
只是为了考试为了让你知道有这种情况 才有这样的填空题的
为了考试那就要知道考试的技巧
看到with那么wtih前面的就是主语
就这样 没错的！^^)