It's very kind____you to give us a talk____the sharks 是不是填of,on?

It's very kind____you to give us a talk____the sharks 是不是填of,on?
It's very kind____you to give us a talk____the sharks 是不是填of,on?

It's very kind____you to give us a talk____the sharks 是不是填of,on?
of,on

他不得不再次问那个男孩：“这条河里没有任何鲨鱼是真的吗？”

of about

yes

是的