【Whatweneedtodois后跟"Whatweneedtodoisverifytheirnucleardeclarationandwehaveputtogetheraprotocolthat'sbasedoninternationalstandards,"HilltoldreporterslateFriday."Ithinkthere'salotofsupportwithinthesix-party】

　　Whatweneedtodois后跟

　　"Whatweneedtodoisverifytheirnucleardeclarationandwehaveputtogetheraprotocolthat'sbasedoninternationalstandards,"HilltoldreporterslateFriday."Ithinkthere'salotofsupportwithinthesix-partyprocessforgettingthisdone."

　　系动词is后面似乎应该跟ing或to,但凭直觉似乎原型很合适.谁能解释一下这里为什么用原型?省略了to的不定式还是什么?

　　省略了to吗？为什么要省？语法上怎么解释？