给出复Grassmann流形G（2，n+2）的全实曲面的一种构造方法，也就是把G（2，n+2）看作$\mathbb{H}$Pn+1中极小子流形Qn+1的商，并证明G（2，n+2）中的曲面可以水平提升到Qn+1中当且仅当它是全实的。
We present a construction of the complex Grassmannian G(2,n+2) as a quotient of some minimal submanifold Qn+1 of $\mathbb{H}$Pn+1, then show that a surface in G(2,n+2) can be horizontally lifted to Qn+1 if and only if it is totally real.
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