若矩阵$\left(\begin{array}{cc}{a}_1& \begin{array}{ccc}{a}_2& a_3& a_4\end{array}\\ b_1& \begin{array}{ccc}{b}_2& b_3& b_4\end{array}\end{array}\right)$满足下列条件：①每行中的四个数所构成的集合均为{1，2，3，4}；②四列中至少有两列的上下两数是相同的．则这样的不同矩阵的个数为（　　）

精子和卵细胞相遇而结合成受精卵的地点是:

将1﹣﹣9这九个数填入右边的九宫格（三阶幻方）中．

    Today I'd like to tell you something about two Chinese festivals.

    The first one is the Mid-Autumn Festival. It is a time for the 1. At night, the whole (全部的) family 2  delicious moon cakes (月饼), and the parents 3 the story of Chang'e. It's a traditional 4 story.

    The second (第二的) one is the Lantern Festival. 5  that day, we eat yuanxiao —a kind of rice dumpling. It's really 6 and I love it very much. We make many kinds of lanterns 7  for the festival. You can see a lot of pictures on 8 some are funny 9 The tiger is my favourite. Well, it likes eating much meat. But I don't want to 10 from it. I want to be healthy.