When the candle burns, first _ _ _ _ _ _ _ _ _ _ _ and then _ _ _ _ _. Why?

When a candle burns, it should be melted first, then vaporized and then burned.

Please observe the candle burning. We can see that the solid melts into liquid wax oil first, and then it is sucked up by the wick. The flame leaves the wick, so flame burning is the way of gas. You can see white smoke from the candle that has just been extinguished.