bywhich和withwhich的区别
bywhich释义： 由 例句： Low levels of straying are crucial, since the process provides a source of novel genes and a mechanism by which a location can be repopulated should the fish there disappear. 低水平的游离是至关重要的，因为这个过程提供了一种新基因的来源和一种机制，通过这种机制，如果该地鱼群消失...