雌性储存精子，可以通过受精或不受精来决定每一个卵细胞的性别。

A female stores sperm and can determine the sex of each egg she lays by fertilizing it or leaving it unfertilized.

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精子与卵子结合开始受精过程。

The sperm fuses with the egg to begin the process of fertilization.

《牛津词典》

进行受精前用显微镜检查精子样本。

The sperm sample is checked under the microscope before insemination is carried out.

《柯林斯英汉双解大词典》

So on the personality theory, I did not exist when that fertilized egg came into being, when the egg and the sperm joined.

所以在人格理论上，卵子受精的时候我还不存在，卵子和精子结合时。

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