Mary was looking at her in the mirror 是“瑪麗正在照鏡子”嗎？
這位網友的翻譯有問題，錯誤就出在代詞用錯了，應該使用“反身代詞”(也叫“自身代詞”)herself，而不是“賓格代詞”her。從語法和邏輯兩方面考慮，如果動作的施事者(發(fā)出者)又充當了動作的接受者，那么必須使用反身代詞，不能使用賓格代詞。因為在同一個句子中，賓格代詞不表示主語本人，而是另外一個人，反身代詞和賓格代詞的差別就在于此。Mary was looking at her in the mirror.這個句子本身不錯，但意思是：瑪麗正在鏡子里看她(網友本人)。
再舉幾個例子，請比較：
She was dressing herself. 她正在穿衣。(給自己穿)
She was dressing her. 她正在給她穿衣。(給別人穿，可能是她女兒)
John should not praise himself. 約翰不應該自吹自擂。
John should not praise him. 約翰不應該表揚他。(表揚別人)
Alice often speaks to herself. 愛麗絲經常自言自語。
Alice often speaks to her. 愛麗絲經常跟她講話。(跟別人講話)
The young man taught himself physics. 那位年輕人自學物理。
The young man taught him physics. 那位年輕人教他物理。(教別人)
She should learn to take care of herself. 她應該學會自己照顧自己。
She should learn to take care of her. 她應該學會照顧她。(可能是自己的妹妹)
Tom bought a new bicycle for himself. 湯姆給自己買了一輛新自行車。
Tom bought a new bicycle for him. 湯姆給他買了一輛新自行車。(給別人買自行車)
下面是一些常見的含有反身代詞的固定詞組，請熟記于心：
abandon oneself to 沉迷于，放縱于 accustom oneself to 習慣于
amuse oneself 自我消遣 come to oneself 恢復知覺
be oneself 狀態(tài)正常 be not oneself 身體不舒服
behave oneself 舉止得體 lose oneself 迷路
dress oneself 穿衣 seat oneself 坐下
devote oneself to 致力于 help oneself to 隨便吃，隨便用
enjoy oneself 過得快活 express oneself 表達自己的想法
feel oneself 感覺正常 teach oneself 自學
think to oneself 心里想 make oneself at home 不要拘束
