The work is so difficult that they don’t know ( ).

So I dont know exactly what she said.一、单项选择题(本大题共20小题，每小题1分，共20分)Choose the best

() 10.Don`t give up,you know "Nothing in the world is difficult for one __ sets

The question is quite difficult, so ________ students can work it out.A. fewB. l

[单选题]（ ）I don’t know __________.A．how often he visits his grandparentsB．how soon will he come backC．how many students are there in his classD．how long is the bridge

I don’t know ( ).A. what does this word meanB. what this word meansC. what kind

[单选题]I don't know ________.A.who were theyB.who they areC.who are theyD.who they

[单选题]Don’t worry.It is not difficult for us to( )the fault.A.spendB.treatC.makeD

[单选题]I don’t know ______ to deal with such matter.A.whatB.howC.whichD./

I really dont knowA. where to chooseB. which to chooseC. to choose whatD. to cho

I really dont know()A. which to chooseB. to choose whatC. what to chooseD. to ch