Over the past decades, the sea ice ______ in the Arctic as a result of global warming.
Shanghai is the first city in the world ____a high-speed maglev train, from the city to Pudong Airport.
——Are you content with her lecture? ——Nowhere near that. It ____.
A British man who ____ to play practical jokes ____ his own humorous art work in four major New York museums over the last two weeks.
I spent the whole day repairing the motorbike. The work was ____ simple.
——Did your classmate accept your invitation? ——No, he ____ refused.