Recent development of the transient surveys and follow-up programs has been forcing us to renew our basic picture of the stellar evolution. Especially challenging is the massive star evolution in their final phases, which manifests itself in observations of supernovae (SNe); the properties of the circumstellar media (CSM) can be translated to the mass-loss history in their final evolution. However, low-resolution observations are biased toward extreme systems with high mass-loss rates, and further they lack kinematical information of the mass-loss mechanism(s). We propose to obtain a time sequence of high-resolution spectra of ∼ 6 SNe as a combination of classical time windows and ToO observations with HDS, covering a range of pre-SN activity down to the level inaccessible by low-resolution observations, coordinated with intensive low-resolution follow-up observations and even with radio frequencies including observations with ALMA. Our program will provide an expanding understanding of the poorly understood nature of the CSM and thereby paint a generic picture covering various progenitors.
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