我妹妹读新单词有困难用英语怎么说

"My sister has difficulty reading new words" 可以用英文表示为 "My sister struggles with reading new words."

"struggle" 是英语中的动词，意思是 "努力，奋斗"。它来源于中世纪拉丁语 "strugere"，意思是 "挣扎"。

例句：

He struggled with the math problem for an hour before finally solving it. (他花了一个小时的时间挣扎着解决数学问题)
She struggled to lift the heavy box. (她挣扎着提起重盒子)
The company has been struggling financially for the past year. (这家公司过去一年一直在经济上挣扎)