______ apple fell from the tree and hit him on ______ head.
Have you had the computer ________ ? You see it really needs ________ .
He is very popular among his students as he always tries to make them ________ in his lectures.
Alexander tried to get his work ________ in the medical circles.
There are some health problems that, when ________ in time, can become bigger ones later on.
In April thousands of holidaymakers remained ________ abroad due to the volcanic ash cloud.