请从语法角度分析一下下面的几个题,尽量说的详细一点.

请从语法角度分析一下下面的几个题,尽量说的详细一点.
1.The British Governor arrived in Australia on January 26,today___as Australia Day.
A.is known B.to be known C.know D.being known
2.___would be many years until Australia recognise the importance of diverse society.
A.That B.There C.It D.They
3.I hear the Oxford Advanced Learner's Dictionary is very useful
.I want to buy___.
A.it B.that C.one D.the one
4.The old man.___abroad for twenty years,is on the way back to his motherland.
A.to work B.working C.to have worked D.having work
5.___it or no,his discovery has created a stir in scientific circles.
A.Believe B.To believe C.Believing D.Believed
就先写这几道题吧,基本上都是非谓语动词的题,请精通英语的高人给我指点!
第1题C为known,第4题D应为having worked
正确答案CCCDA