The flat face and the side face of the plastic hollow brick are provided with a sealing groove, a sealing strip and through holes; the plastic hollow brick can be formed once by pressing.

其构成是塑料空心砖的平面、侧面设有密封槽、密封条、通孔，一次压制成型。

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At first,Andrea Nemethi's face wasn't flat enough for glasses.

VOA: standard.2010.06.30

This is because the new fossil and 1470 share several features, including the flat face below the nose and dental structure, which once led to the species' separation.

BBC: Fossil key to human origins

However, Dr Reich points out, if humans and chimpanzees had undergone an initial separation at this time, it could account for why the skull has human-like features, including a relatively flat face without a protruding snout.

ECONOMIST: Humans could have interbred with chimpanzees

The fact is that today, Facebook at its core, is flat on its face in the mobile world.

FORBES: Facebook Phone Rumors - Social Mobility Is Big Business