There seem to be two main reasons that women cry more often. One is biological. Up to age 12, boys and girls cry equally often. From then until age 18, the level of the hormone prolactin(催乳激素) rises in young women, until their blood contains 60 per-cent more than men' s. And prolactin affects the production of tears. On the sociological side, men in particular are conditioned out of crying. From the age of 12 or 13, boys are told that crying shows a loss of control, that it is a sign of weakness. If men step outside the norm and show their feelings in the workplace, they run the risk of getting labels attached that are not complimentary. Researches on conversations show that women are more likely to talk about feelings, men about activities. This is a reflection of our socialization. Also, men are more likely to express their opinions. It gives rise to women feeling enormous frustration about getting their views across. When women are crying at work, it's often out of sheer frustration, about not being able to get their needs identified, known, put across, and getting a response to them…There is a sense of 'I'm not being taken seriously.' The trouble is, if a woman cries in this situation, men are likely to say, 'She's far too emotional.' There are, though, a couple of arenas(活动场所) in which it seems to be acceptable for men to be emotional: sports and especially more recently, politics. An essay in Times magazine once reported on timely tears from former Presidents George Bush and Richard Nixon. The Times essay says 1988 presidential candidate Patricia Schroeder' s tears led some to describe her as 'just another weak woman, temperamentally unfitted for the presidency'. It concludes: 'Men may weep, but women must prove them- selves made of sterner stuff.' The cause for women crying more often is that______。