A car horn in a dream indicates the need to pay attention to an awkward situation in our life. It can also express anger or the need to be assertive towards a certain person.
to see - someone will tell you loud news that will make you unpleasantly surprised
use it - regardless of the circumstances, you will introduce someone deliberately mislead
car horn - you will lose control over a certain situation
bicycle horn - someone will want to attract your attention.
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