While there is advice aplenty on how to lose pounds or kilograms, a new study focuses on middle aged and older women who maintain normal body weight, or BMI (Body Mass Index) and do not diet.

VOA: standard.2010.03.30

A second implicit purpose for the youngster-aged group is a baby-sitting purpose.

对青少年群体来说,第二个深层目标,充当临时保姆。

麻省理工公开课 - 媒体、教育、市场课程节选

A second implicit purpose for the youngster-aged group is a baby-sitting purpose.

对青少年群体来说,第二个深层目标,充当临时保姆。

麻省理工公开课 - 媒体、教育、市场课程节选