The official said rescuers were working_____to find the missing miners in the coal mine blast

_________ the help of man-made satellites,we can know what the weather will be like in the next few days.

_____ the city’s public school system should be open to the children of migrant workers has become the focus of discussion

I thought you ____ like something to read , so I have brought you some books .

What are Mr. and Mrs Black doing They_____tea in the garden.