为什么是picked it up,而不是picked up it

为什么是picked it up,而不是picked up it 为什么是mix it up而不是mix up it? picked it up 如题 What makes it move up and down?为什么是move而不是moves?it不是单三吗? 为什么是pick it up 而不是pick up it感觉很迷茫.谁可以浅显地给我讲一下? 哪位高人可以帮我看下这个题1.After ____ to me ,she picked it up.(apologize) 这个为什么是填apologizing?(to 为什么是cheer you up而不是cheer up you 为什么是work on it而不是work it on?也有cup them up啊!这些怎么区分? 为什么是work on it而不是work it on?也有cup them up啊!这些怎么区分? picked up he saw a penny on the ground.He picked it up and happily put it into his pocket.The penny was his,and it cost him nothing 最后这个为什么是nothing A loy picked it up,and laid it in the He picked it up and put it under the coat. He picked it up and put it under the coat. stay up为什么是“熬夜”而不是“坚持向上”或者其他 He saw something on the ground and __________.A.picked them upB.picked it up 用picked and it up carried bag the I造句 we picked it up……这句话是什么意思?we picked it up,made snowballs and threwthen ateach other