根据以下内容回答题: Hostility is the urge to harm another person or oneself in the expression of anger．Anger is an anxiety defense reaction to anything perceived as a physical or emotional threat to sectirity，status，or self-image．Because the need to feel worthy and respected is natural to human beings，and because life is filled with chaHenges，every person feels angry sometimes．But the expression of anger depends on an individual’S psychological make up，and can range from mild irritation to uncontrolled great anger． Internal psychological factors are the sources of anger；environment"al factors bring these out by stimulating vulnerable areas conditioned by the peculiar emotional interpersonal relation-ships of individual childhood．If a baby receives hostility instead of the love and affection he or she craves，the baby defends himself or herself with anger：When his or her shows of anger constantly move others to more anger，he or she learns to repress his or her feelings．Repress-ing anger hides it and its causes from conscious awareness，and makes its expression unpredict-able，less easy to control，and more impulsive．Impulsive expressions of anger，therefore，indi-cate suppression of deep feelings．Explosive“letting off steam”is a way of convincing oneself and others of the seriousness of provocation and the power of anger．It also relieves the pressures of underlying anxiety to a more tolerable level． The strong energy of anger can be used in coristructive rather than destructive ways．It is healthy to release anger through non—injurious physical activity and the overcoming of frustration in achieving personal goals．By examining his or her feelings and reactions，a person can team to free himself or herself from the negative energy of anger． It can be inferred from the passage that hostility in．the expression of anger is__________ ．