这样的2维宇宙模型就像是球体，不可能出现平行的测地线(测地线是曲面上的直线)——两直线必然在某点相交。
A two-dimensional model of such a universe would look like a sphere. It's impossible to have parallel geodesics (straight lines on a curved surface) — the two lines will cross at some point.
观察脑袋的轮廓和口吻的轮廓，是两条大致平行的直线，长度大致相等，被一个非常轻微，但可察觉的止部分隔开。
Viewed in profile the top of the skull and the top of the muzzle lie in two parallel, straight lines of equal length, divided by a slight, but perceptible "stop" or break.
观察脑袋的轮廓和口吻的轮廓，是两条大致平行的直线，长度大致相等，被一个非常轻微，但可察觉的止部分隔开。
Viewed in profile, the top of the skull and the top of the muzzle lie in two parallel straight planes of equal length divided by a slight, but perceptible "stop" or break.
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