Abstract　 　　
　 I present spectral imaging observations of chemical abundant source (Sgr B2) by use of the interferometer first which are crucial to astrochemical study, since the emission position of a specific molecule may indicate its forming mechanism, i.e, different molecular species may form at different positions of the cloud.  

    Unhindered by the atmosphere, many molecular species cannot be observed directly from the ground telescopes. Herschel/HIFI scans open up new spectral windows towards the sources that have characterized the spectrum accessible from the ground, which will impose a severe limitation on interpreting previous observations. Thus in this talk, I mainly present the molecular line observations toward Sgr B2 using the Herschel/HIFI. The Herschel/HIFI full frequency range is from 480-1250 GHz and from 1410-1900 GHz. The large bandwidth of Herschel/HIFI observations reveals many molecular transitions; even for a specific molecule, hundreds or thousands of transitions are detected spanning a wide energy range that sample a wide range of environments, which will be useful in exploring physical and chemical differences among different positions of the cloud. On the other hand, the large bandwidth of the Herschel/HIFI observations will be helpful in identifying the molecular lines and kinematics of the star forming regions.