英語里一般是不會(huì)出現(xiàn)“who who”的,要盡量避免使用兩個(gè)相同的引導(dǎo)詞.所以最好說“who that”.
你的第一個(gè)句子的提問應(yīng)該說“Who is from America that likes music?”或者“Who likes music that is from America?（更好）”
而第二個(gè)句子應(yīng)該問“Who is Tim talking to that is writing an e-mail?”或者“Who is writing an e-mail that Tim is talking to?”