It can take up three months to _____ a man to do this work.

 His blood type is so rare (稀有) that it’s difficult to find any type to _______ his.

I tried to persuade him not to keep in touch with her, but what I said was always ______.

People in Tibet are ________ than they used to be.       

If we can___our present difficulties,then everything should be all right.