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It is a longstanding problem that HII regions and very young stellarpopulations in the Large Magellanic Cloud (LMC) have the nitrogen abundances  ([N/H]) by a factor of ~7 lower than the solar value. We here discuss a newscenario in which the observed unusually low nitrogen abundances can be closelyassociated with recent collision and subsequent accretion of HI high velocityclouds (HVCs) that surround the Galaxy and have low nitrogen abundances. Weshow that if the observed low [N/H] is limited to very young stars with agesless than ~10^7 yr, then the collision/accretion rate of the HVCs onto the LMCneeds to be ~ 0.2 M_sun/yr (corresponding to the total HVC mass of 10^6-10^7M_sun) to dilute the original interstellar medium (ISM) before star formation.The required accretion rate means that even if the typical mass of HVCsaccreted onto the LMC is ~ 10^7 M_sun, the Galaxy needs to have ~2500 massiveHVCs within the LMC's orbital radius with respect to the Galactic center. Therequired rather large number of massive HVCs drives us to suggest that the HVCsare not likely to efficiently dilute the ISM of the LMC and consequently lowerthe [N/H]. We thus suggest the transfer of gas with low [N/H] from the SmallMagellanic Cloud (SMC) to the LMC as a promising scenario that can explain theobserved low [N/H].

Origin of the unusually low nitrogen abundances in young populations of the Large Magellanic Cloud