( ) 17. In those days, whenever I had difficulties, I _______Mr Shen for help.
---He has been working hard all the time. ---__________ he got full marks in the last English test.
As we can see, the prices of vegetables _____ according to the season.
Come and see me whenever ____.
From these facts we can _____ a conclusion that no one can prevent us from becoming stronger.
He is such a strong-willed person that there is nothing in the world that can _____ him.