This is just a very short exercise introducing the "metaphor". The "metaphor" is another way of painting a more colourful picture. Instead of using "simile" to liken something or somebody to something else, the "metaphor" takes the place of that something or somebody (leaving it up to the reader/listener to view the picture in his head).
Short example:
Metaphor: The floating sails of the horse-chestnut tree fluttered in the wind.
Simile: The horse-chestnut tree's leaves and branches floated in the wind like the sails of a ship.
If you like the "simile" points the reader/listener more directly to the picture but the "metaphor" allows the reader/listener to create his own picture.
Now look at the phrases below and decide if they are "metaphors" or "similes"