时态看谓语动词.这句话的谓语动词是had,是have的过去式,所以是过去时Mymotherusuallycutthemeat intopiece.改为否定，一般疑问句这句话的cut是过去式，因为my mother 是第三人称单数，后面的谓语动词不会用原形，只能是三单或过去式。而cut不是三单，只能是过去式否定 My mother didn't usually cut the meat into pieces.一般疑问 Did your mother usually cut the meat into pieces?