只有ing應該出現在expert at之後嗎?
母語人士的回答
Rebecca
是的,因為expert at必須後跟名詞,在這裡你必須使用動名詞(以動詞的一個形式的名詞ing名詞)或另一個名詞。示例: She is an expert at horseback riding. ( She is an expert at basketball.騎馬She is an expert at basketball. 。)示例: She is an expert at basketball. (她擅長籃球。)