1、如E大所说有两种说法：
1）成为新生儿，有新的父母，然后慢慢恢复记忆
In this discussion he referred in rapid and elliptical expression to the difficulties at every level(including practical and psychological) in the idea of the reincarnationof the fea as the newborn child of second parents, who as it grows up recaptures the memory of its previous life: 'the most fatal objection' being that 'it contradicts the fundamental notion that fea and hroa were each fitted to the other: since hroar have a physical descent, the body of rebirth, having different parents, must be different', and this must be a condition of pain to the reborn fea.
2）被一如重制身体
The other mode is the making, by the Valar, of 'such a house in all particulars as it had ere evil befell it': the reincarnation of the Dead in a hroa identical to that which death had overtaken.
'The only solution,' he decided in this discussion, was the idea of the remaking in identical form of the hroa of the Dead in the manner declared by Eru in The Converse of Manwe and Eru: the fea retains a memory, an imprint, of its hroa, its 'former house', so powerful and precise that the reconstruction of an identical body can proceed from it.
具体见HoME，Morgoth's ring.
2、Morgoth创造有自由意志的生命这的确是不可能做到的，我估计也是将一如的作品加工改造得到的。比如将巨蟒、巨蜥、甚至神灵等经过腐化、杂交、融合、同调召唤、超量召唤、改造、培育、变异等一系列不可知的复杂生化程序最终得到。（游戏王乱入+口胡- -）

刚才又看了下，貌似重制身体还简单点，Valar就可以全权处理；
而如果精灵想要选择另一种方式以新生儿的形态重生，不仅Manwe要同意，还需要上报Eru取得他老人家的批准，够麻烦的。。。小小精灵而已，用的着每一只都去惊动Eru他老人家吗
Eru said: 'I give you authority. The skills ye have already, if ye will take heed. Look and ye will find that each spirit of My Children retaineth in itself the full imprint and memory of its former house; and in its nakedness it is open to you, so that ye may clearly perceive all that is in it. After this imprint ye may make for it again such a house in all particulars as it had ere evil befell it. Thus ye may send it back to the lands of the Living.'
Then Manwe asked further: '0 Iluvatar, hast Thou not spoken also of re-birth? Is that too within our power and authority? '
Eru answered: 'It shall be within your authority, but it is not in your power. Those whom ye judge fit to be re-born, if they desire it and understand clearly what they incur, ye shall surrender to Me; and I will consider them.'

干豆腐重生之前肉体也烧坏了啊，可是重生时又玩好如初

总结整理了下，有两种方式，有新父母“reborn”或是重塑身体“remade”。
在早期的“Laws and Customs”当中托老设定的似乎是“reborn”为唯一普遍的方式，除了Miriel可以重返自己原来完好无损的身体作为特例。
然后不久托老写下了“The Converse of Manwe and Eru”,提到之前并没有精灵复活现象，直到Miriel事件后Manwe向Eru问询，Eru提出允许精灵复活，而“reborn或是remade两种方式皆可”，remade可由维拉全权处理，reborn则必须取得Eru本人同意。
但在此之后托老的记述中却把reborn否定了，并再未提到过。因为托老认为无论实践上还是心理上这种被新父母生育再获得前世回忆的方式都是很艰难的、痛苦的，更违反了肉灵结合的和谐性。所以“remade”反而被保留为the only solution.
尽管如此The Converse of Manwe and Eru的概念并未被完全舍弃，即在大乐章时期Eru并未考虑到精灵死亡的问题，精灵死后只是聚集在Mandos殿堂。直至Miriel事件后Manwe向Eru问询，Eru告诉Manwe对Melkor的政策并提出允许精灵复活。然而，其中reborn的概念仍在之后讨论中被完全舍弃，remade被作为唯一方式。
所以龙堡里翻译的那篇资料是不确切的，曾经在一如的帖子里误导过某位同学表示抱歉 @爱拜仁4ever 

学术党大神