Tom was about to close the window　　　　 his attention was caught by a bird.

To enjoy the scenery, Irene would rather spend long hours on the train _____ travel by air.

It is obvious that people hold different opinions about ____ voluntary services should be financially rewarded.

It suddenly _________ to the detective that the millionaire was probably murdered by his own daughter.

It is the first time that I _______ this kind of moon cake.