I don't think that anyone else in my country is qualified to take over his seat.

qualified 是动词 qualify 的过去分词形式，在这里作形容词使用。qualify 由词根 qual（质量、资格）和后缀 -ify（使成为）组成，意思是"使具备资格"。qualified 表示"具备资格的、符合要求的"。