Some\tof\tthem\tbe\tbig\tand\tsome\tof\tthem\tbe\tsmall .
some\tof\tthem\tbe.HAB\tbig\tand\tsome\tof\tthem\tbe.HAB\tsmall
Generally, some of them are big and some of them are small. OR: It is usually the case that some of them are big and some of them are small.