If you observed a four-year-old child, for example, my daughter is 4 years old; you might read up on Piaget's stages of cognitive development we covered those in class.

如果你观察一个四岁的孩子，例如我四岁的女儿，你可能要先研读皮亚杰的认知发展阶段理论，这一理论是我们在课堂上讲过的。

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I lived in Hungary as a child, but my family had to leave when I was fourteen years old.

我小时候住在匈牙利，但在我14岁的时候，我的家庭不得不离开。

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Death is always a painful subject especially for a seven-year-old child who'd lost his mother only two years before.

死亡总是一个令人痛苦的话题，尤其是对一个两年前刚刚失去母亲的七岁孩子来说。

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Anna Carpenter is thirty-three years old and busy with work, a husband and soon a child.

VOA: special.2010.12.27

Our youngest child Neil who is 15-years-old, is starting InnovationGeneration to inspire young people to get interested in science and use innovations to solve grand challenges.

FORBES: The Source of My Greatest Happiness Has Always Been Our Children

The child, thought to be about 10 years-old, suffered "significant" head injuries in the accident on London Road, Bath, at about 16:00 GMT, South Western Ambulance Service said.

BBC: Boy struck by ambulance on 999 call in Bath

Investing in education If you invest in a child's education - maybe they're five years old when they start, and maybe they're in their early 20s when they get out of university - that's a long time.

BBC: News | Monitoring | President Clinton on Shanghai radio phone-in