The most frequent symbols that appear in dreams - such as water, vehicles, death or snakes - highly depend on the dream's context and details for their meaning. For example, death generally represents change, and other people represent certain parts of ourselves. Therefore, if someone kills another person in a dream, it may mean that she is letting go of the part of herself associated with the other person.
A dream about snakes generally relates to the unconscious mind, masculinity, transformation and healing. However, the dreamer should consider her feelings towards snakes, as well as any past experiences or recent thoughts about snakes. Snakes also represent intuition and higher perceptions, so their symbolic meaning may also stem from the dreamer's instinct or spiritual self.
Water in dreams is generally associated with emotions, feelings, purification and change. If a person is underwater in a dream, she may be overwhelmed by emotions or by changes in her life. If she feels comfortable underwater, it means that she enjoys her intense emotional state and lack of control. A fountain or clear water generally refers to a rejuvenated state of mind. Calm waters represent serenity and peace, indicating that the dreamer is in tune with her subconscious.
Dream interpretation is a personal process, shaped by the dreamer's experiences, perceptions and mentality. Universal meanings of symbols should be used only as guidelines.