they are 后面加什么
There are句型后面应该加复数名词，作真正的主语。
There are several conjectures.
有几种推测。
There are two codes for London.
伦敦有两个电话区号。
There are three winning tickets.
有三张中奖的彩票。
There are no hidden extras.
没有任何隐蔽的额外费用。
There are mountains to the north.
北面有山。
There are many species of dog(s).
狗有许多种。
There are 31 days in May.
五月份有31天。