Star formation is crucial to the Universe in many ways. Among the key questions
in star formation, the birth of massive stars and the origin of stellar initial
mass function are the two outstanding issues to be conquered. I will introduce
how I have been tackling the two questions by observing Galactic molecular clouds,
thanks to the recent development in mm/sub-mm interferometry and far-infrared
imaging and polarimetry. I will discuss how ALMA can play a pivotal role in
surveying the earliest stage of star formation. The survey capability will
help to answer a few fundamental questions about star formation when combined
with SOFIA, JWST, and ngVLA.