Level 50: We are not allowed to enter this construction site. A block of flats is being built here and it is dangerous to walk because you may get hurt by a fallen brick or some other objects.

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Explanation: fallen (adj): fallen

Edit: fallen -> falling (adj): falling

Translate:

We are not allowed to enter this site. An apartment complex is under construction here and it is very dangerous to walk because you may get injured by a falling brick or some other object.