—Minister, are you satified with the performance of the Chinese athletes in Beijing Olympics? ---Yes, it couldn't have been _____.
The plane is flying ____ a speed of 500 kilometers an hour ____ the way to Kunming.
You can’t learn to play the piano without practising.____, you can’t learn a language well without using it.
We’ll ____ three groups to carry out the experiment in chemistry.
He fell from the bike and broke his leg.____, he will have to be away from school for two or three months.
When the plane ____, all the passengers on board should turn off their mobile phones.