The primitive root of the pleasure of parenthood is two-fold. (46) On the one hand, there is the feeling of part of one’s own body externalized, prolonging its life beyond the death of the rest of one’s body, and possibly in its turn externalizing part of itself in the same fashion, and so securing the immortality of the germ plasma. On the other hand there is an intimate blend of power and tenderness. The new creature is helpless, and there is an impulse to supply its needs, an impulse which gratifies not only the parent’s love towards the child, but also the parent’s desire for power. (47) So long as the infant is felt to be helpless, the affection which is bestowed upon it does not feel unselfish, since it is in the nature of protection to a vulnerable portion of oneself.
(48) But from a very early age there comes to be a conflict between love of parental power and desire for the child’s good, for, while power over the child is to a certain extent decreed by the nature of things, it is nevertheless desirable that the child should as soon as possible learn to be independent in as many ways as possible, which is unpleasant to the power impulse in a parent. Some parents never become conscious of this conflict, and remain tyrants until the children are in a position to rebel. Others, however, become conscious of it, and thus find themselves a prey to conflicting emotions. In this conflict their parental happiness is lost. (49) After all the care that they have bestowed on the child, they find to their mortification that he turns out quite different from what they had hoped. They wanted him to be a soldier, and they find him a pacifist, or, like Tolstoy, they wanted him to be a pacifist, and he joins the Black Hundreds.
But it is not only in these later developments that the difficulty is felt. (50) If you feed an infant who is already capable of feeding himself, you are putting love of power before the child’s welfare, although it seems to you that you are only been kind in saving him trouble. If you make him too vividly aware of dangers, you are probably actuated by a desire to keep him dependent upon you. If you give him demonstrative affection to which you expect a response, you are probably endeavoring to grapple him to you by means of his emotions. In a thousand ways, great and small, the possessive impulse of parents will lead them astray, unless they are very watchful or very pure in heart.
(46) On the one hand, there is the feeling of part of one’s own body externalized, prolonging its life beyond the death of the rest of one’s body, and possibly in its turn externalizing part of itself in the same fashion, and so securing the immortality of the germ plasma
参考答案：
一方面是觉得自己肉体的一部分能够永久存在，使它的生命在肉体的其余部分死亡之后延长下去，而这一部分将来可能以同样方式再延长一部分的生命，由此使细胞永生。
解析：
这是一个简单句，句架是..., there is the feeling of part of one’s own body externalized，prolonging...，and...externalizing..., and so securing...。句中出现了三个现在分词短语，用作方式状语。而externalized是过去分词，作后置定语。句中externalize的意思是“给……以外形，使客观化，使具体化”，secure的意思是“获得，得到”，immortality的意思是“不朽，永生”，germ plasma的意思是“细胞体，微生物体”。