Beware! Dangers abound. So do warnings.
Sometimes the warnings are very wordy:

Danger of lightning, of rabies, of swimming, of plummeting down a ravine, or simply of a gate.
Sometimes pictograms seem enough:

No jumping (deadly peril!), no slipping, no driving into trees. And beware of sudden drops, strong currents, submerged rocks, deep water, large waves, giant frogs, and elderly people!
But the biggest danger of them all:

Beware of children!
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