Only when the final examination was coming ________ he had quite a lot to do.[ ]

Mr. Brent is a man with _______ personality—he never seems tired with so much work to do every day.

Having walked in the desert for several days，we finally reached what was called oasis，________

Having checked the doors were closed, and ________ all the lights were off, the boy opened the door to his bedroom

The most pleasant thing of the rainy season is _____ one can be entirely free from dust.