Answer and Explanation:
The signs that prevent us from swimming on the beach are signs that indicate some kind of danger, which can compromise our life, the well-being and the fun that the beach can provide. In other words, these signs are danger signs and are presented to keep us safe. The last time I went to the beach, I saw a sign that forbade people from entering the water because there were sharks in it, but recently, we can see many signs that prevent us from entering places without wearing a respiratory protection mask. This is done as a prevention to coronavirus.