有谁能帮我解答这四道英语选择题?还有选择答案的理由

有谁能帮我解答这四道英语选择题?还有选择答案的理由
1 I would rather ( ) the professor and I would rather you( ) for him at once.
A invite sent B invited send C inviting sending D invite sending
2 there is a felling in me( )we will never know what a UFO is.
A that B which C of which D what
3 the boys are not doing a good job at all,are they?( )
A I guess so B I don’t guess so C I don’t guess D I guess not
4 if you compare food costs today( ) of a year ago,you will find the difference.
A to that B to them C with that D with those