必修: (of an academic course) required, compulsory...
上瘾: to get into a habit, to become addicted...
舰艇: warship, naval vessel...
格式: form, specification, format...
惹祸: to stir up trouble, to invite disaster...
剩下: to remain, left over...
广阔: wide, vast...
灯泡: light bulb, see also...
乐观: optimistic, hopeful...
炊烟: smoke from kitchen chimneys...
