In view of the worsening environment, the local government is seeking advice from Professor Smith, who is an expert ______ it

that he managed toget the information?— Oh, a friend of his helped him.[ ]

Tom’s dog became ill and died,____ made him very lonely.

Have you finished your work yet　—No, not yet. I think it’ll take _____ ten minutes.　 more

______ is impossible if you put your heart into it and try your best.