1.本句叙述的是一般事实:Animal experts 是句子的主语;in Coratia是定语,修饰主语;say谓语;a bear has learned how to.是宾语从句;在宾语从句中:a bear是主语;has learned谓语;how to trick people to let him in是宾语;by knocking at the door是方式状语.
2.本句为虚拟语气,if条件句用一般过去时,主句谓语动词用would+动词原形.
1.本句叙述的是一般事实:Animal experts 是句子的主语;in Coratia是定语,修饰主语;say谓语;a bear has learned how to.是宾语从句;在宾语从句中:a bear是主语;has learned谓语;how to trick people to let him in是宾语;by knocking at the door是方式状语.
2.本句为虚拟语气,if条件句用一般过去时,主句谓语动词用would+动词原形.