If you stand under a tree during a thunder storm the lighting will hit the tree and a ground charge will spread out from the tree in all directions.
Do NOT stand under a tree during a thunder storm
If you put a metal objects into a microwave the sharp metal objects can spark in the microwave. Metal also heats up very quickly which causes it to melt and spark.
Never put anything metal into a microwave
It's not safe to throw electric things in the water.
If you throw wires in the water and some one is in it they will be electrocuted. This is also because water is such a amazing conductor.