1 Jenny and li Ming get the train 这句话所要表达得意思为珍妮和李明上了车或者下了车.应改为Jenny and li Ming got 【on / off 】the train.已经乘了车或者已经下了车,故要用过去式.get on/off 为固定短语 意为 上车/下车.
2 This sweater is expensiver than that dress.这句话所要表达的意思是这件毛衣比那条裙子要更贵些.应改为This sweater is more expensive than that dress.这里是将毛衣和裙子作比较,故要用比较级,而expensive 是多音节形容词,它的比较级必须要在其前面加上more（“更”）构成,不能再后面直接加上er,最高级也如此.
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