問題詳情:
He became a famous writer when he was ______ .
his fifty his fifties fifty years old fifties
【回答】
B 表示具體的歲數時,可用at+基數詞或者at the age of+基數詞。表示某個年齡段時,要用in one’s+基數詞的複數形式。故選B。
知識點:介詞和介詞短語
題型:選擇題