We walk ( ) the park and enjoy our meal under a big tree at

B,walk to the park,步行去公园.walk在这里是不及物动词,后面要跟宾语的话要加介词,其他的都是介词,walk across是从某处的表面走过,walk between是从两个物体之间走过,walk through 是从物体内部穿过,walk to是走到某地去,表示方向.