This is the only way that I can think of _______ the problem of water waste in urban areas.
21. At first she was not accustomed to _________ in the new company, but eventually she managed to get through and get on well with her companions.
20. In many places in China, ____ bicycle is still _____ popular means of transportation.
19. My grandpa has many hobbies which _________ from collecting stamps to planting flowers.
18. It was ______ back home after the experiment.
17. -- My mother always tells me to try my best _______ many difficulties. -- I can’t agree any more. _______ you put your heart into work, you can overcome them.