Products made in this factory ____well; they have sold ___all their products

Mary and Joy are ____ Class One. They are ____ the USA.

Does China have cultural relics?— Yes, it is admitted that many cultural relics in the world, such as the Great Wall, the Potala Palace, the Magao Caves and so on, ______ China

orked with children before,so I know what _________ in my new job.

Miss Wei often helps us ________ our English.