My sister is better at study than I.同义句

原句是：我姐姐比我学习好.
直接同义：I'm worse at study than my sister.【我比我姐姐学习差.】
间接同义：I‘m not as good as my sister at study.【我没有我姐姐学习好.】I am not ___ ____ ___ study as my sister. 按这个形式翻下，辛苦一哈...I am not so good at study as my sister.不辛苦，嘻嘻。