They fell in love with each other the first time () they met at a birthday party.1)不填 2) at which
1)不填 2) at which 3)that 4）when 四個(gè)選項(xiàng)哪些是正確的,并能說(shuō)明一下選擇的理由,
應(yīng)不止一個(gè)選項(xiàng)是正確的。但大家都選了一個(gè)，難道真的只有一個(gè)選項(xiàng)是正確的。