11. When I was sixteen, I had to _________ before graduation and work in a clothes shop to help support my family.
Rather than ______ on a crowded bus, he always prefers _____ a bicycle.
He has devoted most of his time and energy _______ a cure for the disease.
The child asked his mother _______ go out to play tennis.
– Do you know the West Lake in Hangzhou? – Yes, this is the third time that I ____ this beautiful city.
It was a really ________ experience. Afterwards everybody was very _________.