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。

youdao

She used the royalties to purchase a run-down farmhouse in New Hampshire, where she raised four children without the aid of electricity or running water until her youngest child was five years old.

她用所获得的版税购置了一座位于新罕布什尔的古旧农舍，她在那里抚养四个孩子长大，直到她最小的孩子五岁之前农舍都无法使用电和自来水。

youdao

Here is a child of three years old, and she cannot tell who made her!

这是个三岁的孩子，可她根本说不出是谁造出了她！

youdao

Researchers from Boston Children's Hospital in Massachusetts found a doubling in the odds of obesity by the time the child was three years old.

BBC: C-section 'may double risk of childhood obesity'

Ms. Chiang, 93 years old, is today celebrated as the Julia Child of Chinese cuisine.

WSJ: Cecilia Chiang, the Queen of Chinese Cuisine

If you have a low-income relative, or a child who will be at least 19 years old by the end of the year in which the securities will be sold (24 for full-time students providing more than half their income), consider gifting the securities to the relative or child now and having the recipient sell the securities at his or her lower rates.

FORBES: Year-End Tax Planning Tips For Stock Options And Restricted Stock