—Do you have any idea why the engineer resigned?—No. In fact, everyone is ____about it.

 The boy is ______ computer games and stays in the Internet cafe all day and night.

After two years’ research, we now have a ________ better understanding of the disease. 

The new secretary is a quick, _______ worker, and the boss is quite satisfied with her.

Train services are usually ________ and run regularly every day.