The present invention relates to crystalline polymorphs of (2-(4-(2-(1-isopropyl-3-methyl-1H-1,2,4-triazol-5-yl)-5,6-dihydrobenzo[f]imidazo[1,2-d][1,4]oxazepin-9-yl)-1H-pyrazol-1-yl)-2-methylpropanamide (GDC-0032, taselisib), methods of use, and processes of preparing thereof.本發明係關於(2-(4-(2-(1-異丙基-3-甲基-1H-1,2,4-三唑-5-基)-5,6-二氫苯并[f]咪唑并[1,2-d][1,4]氧氮呯-9-基)-1H-吡唑-1-基)-2-甲基丙醯胺(GDC-0032,塔西利昔(taselisib))之結晶多晶型、其使用方法及製備方法。