A US report predicts that in 15 years' time the economy in Asia will be larger than ________ of North America and Europe combined.
After half a year’s training, they were made entirely used ____ underwater.
Thank you very much for the trouble you have taken _________ me with my English.
Before the conference, a new problem came up __________ could speak on behalf of our group.
He dressed up and went to the party as if ___________.
Scientist are not sure about the ___________ of water on the Mars.