能引起人产生抗体的病原体，叫____。
16里面有____个十和____个一。
(____) These are all books about science.
(____) That's a good idea.
(____) Let's put them on this shelf.
(____) We can put them on Shelf B.
(____) Let's make a home library.
里填上＞、＝、＜．