The temperature at which liquids change into vapours is very high, for example, water vaporises at l00C then how is n possible for water to evaporate at room temperature or at any other temperature?
The molecules of water present on the surface of the exposed area which are in very small fraction, gains the energy from the surrounding. With this higher kinetic energy they are able to break the force of attraction between them and hence get converted into vapour state.
This phenomenon of change of a liquid into vapours that takes place at any temperature below its boiling point is called evaporation.