Given a control system on a smooth manifold, any admissible control function generates a flow, i.e. a one-parametric family of diffeomorphisms. We give a sufficient condition for the system that guarantees the existence of an arbitrary good uniform approximation of any isotopic to the identity diffeomorphism by an admissible diffeomorphism and provide simple examples of control systems that satisfy this condition. This work is a joint work with A. Sarychev (Florence) motivated by the deep learning of artificial neural networks treated as an interpolation technique.