Now most families have only one child _____ our country’s one-child policy.
He had to retire(退休) early ______ poor health.
One of the most interesting places in Yangzhou ________ are often visited by foreigners is the West Slender Lake.
—I can’t find Mary. Where’s she?—Sorry, I don’t know ______.
—Is the film interesting?—I thought it would be. But ______, it’s very boring.
—______ did you sleep last night?—Only five hours. I stayed up late to do my homework.