The happy ________ of children playing in the garden disappeared, and it was quiet again.

There is nearly five thousand dollars         of goods in the shop.

As the quality of the city’s air continues to give rise to ______, the residents are encouraged to set off fewer fireworks.

The system has been designed to give students quick and easy ____  to the digital resources of the library.

Working hard is not only a_____ of a great success, but is among the essential requirement.