单项选择题
A．She was a teacher. B．She was a visiting farmer. C．She was a journalist writing articles about China. D．She was a business woman helping her father with his business.
A．before seven years old B．from birth to three years old C．in his childhood D．in his teens
A．the phenomenon of birds dozing in pairs is widespread B．birds prefer to sleep in pairs for the sake of security C．even an imagined companion gives the bird a sense of security D．a single pet bird enjoys seeing its own reflection in the mirror