春节前后,哈尔滨举办冰雪节,而广州举办迎春花会,造成这种差异的主要原因是( )
A:海陆位置
B:纬度差异
C:地形差异
D:地势高低
The workers ____ (build) a new bridge near my house last year and I guess they will finish it next month.
蝗虫的体表有外骨骼,外骨骼的作用是____和____内部柔软器官,为防止体内____蒸发,更好地适应____生活.