The companies are working together to create ________ they hope will be the best means of transport in the 21st century.

From May 6, pedestrians() 10yuan if they run red lights, according to Beijing traffic authorities.

______ do you visit your grandparents— Every two weeks.

Most animals and plants are _______ large or sudden changes in temperature, so the ocean is a safe and comfortable habitat.[ ]

Unless _________ by the police, you should keep silentover the accident.