Could　you　please　rephrase　that　question/topic?　　　
    I'm　not　exactly　sure　what　you　mean　...
    I'm　not　exactly　sure　how　to　answer　that　question,　but　(perhaps)　...
    That's　a　rather　difficult　question,　but　(maybe)　...
    I'm　sorry,　but　I　don't　know　much　about　...　　　　　　　　　　　
    However,　it　might　be　possible　that　...　
    Maybe　I　can　answer　your　question　by　telling　you　about　a　personal experience　I　had.　
    That's　an　interesting　question　...　　　　　　　　　　　　
    Let　me　see.　Well,　I　suppose　that　...
    Well,　I　think　there　are　2　(or　3　or　more)　reasons:　　　　　　　　　　　
    First,　...　Second,　...　Finally,　...
    In　my　opinion　there　are　three　ways　of　looking　at　it:　　　　　　　　
    First　of　all,　...　Next,　...　Then,　...
    Have　I　given　you　enough　information?　
    Would　you　like　me　to　tell　you　more　about　...?
    Is　that　all　you'd　like　to　know?
    I'm　afraid　that's　about　as　much　as　I　know.
    I　think　that's　about　it.
    I　can't　think　of　anything　else　right　now　...