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Cold molecular gas is a key component in galaxy evolution, as it forms stars, bears feedbacks, and feeds supermassive blackholes. Interferometric observaions of the Atacama Large Millimeter/submillimeter Array (ALMA) have remarkably advanced this field in the past decade. For spiral galaxies, a larger sample with higher physical resolution than before is systematically surveyed. I will discuss the molecular gas morphology and kinematics in three megamaser (Seyfert-II) galaxies at resolutions of around 100 pc. We found prevelant irregularities, potentially related to active galactic nucleus feedback and supermassive blackhole feeding. For early-type galaxies, it is now feasible to spatially resolve giant molecular clouds (GMCs). I will talk about GMCs at 15-pc resolution in the lenticular galaxy, NGC1387. Their dynamical states (Larson relations, virial parameters, etc.) are surprisingly similar to those in spiral galaxies. For our own Milky Way centre, a new ALMA large programme has mapped the central molecular zone (CMZ) at unprecedented spatial (sub-pc) and spectral (0.2 km/s) resolutions. Here, we found evidence of galactic shear effects and magnetic fields driving gas structure morphologies. I will conclude by summarising the physical drivers of molecular gas properties at different scales and in different environments.