Mr. Lin gave us some _____ how to learn English well last week.

If you go to visit London, don’t forget your _________ because it rains a lot.

John wants to be a     , so he often helps sick people in the hospital. 

When I hurriedly got to the airport ,the lady at the window told me that there were no________ left on the plane.

_______ wear white uniforms and help doctors in hospital.