Along with gravity, thermal processes, and magnetic field, turbulence is a key factor in ISM evolution and star formation. Characterizing turbulence in astrophysical settings has been challenging, largely due to the incompleteness of dynamic measurements and the coupling between motion and position on the sky. For molecular clouds, in particular, we (Qian et al. 2012, 2015) have developed a new method, namely Core-Velocity-Dispersion (CVD), which is shown to be related to the two dimensional structural function. CVD holds the promise to provide a rare, direct measurement of the turbulence energy dissipating rates in clouds. We also obtained energy injection rate from star formation in Taurus (Li et al. 2015). It is surprising that even in such an exclusively low mass star-forming region, the turbulence can be sustained solely by star formation feedback. Using ALMA, we discovered subsonic turbulence in massive star forming regions and revealed its resolution-dependent nature down to thermal Jeans scale, for the first time (Yue et al. 2018). Our work help provide systematic characterization of turbulence and its role in star formation.