今天我们要学的词是thorny。Thorn, 本身是刺的意思，而thorny, 变成形容词，意思是棘手的，富有争议的。最近美国联邦贸易委员会宣布要对facebook脸谱网站是否侵犯用户个人隐私进行调查。 "Facebook's privacy problem has always been a thorny issue," 脸谱网站的隐私设置一直是一个有争议的议题。 "In the post Cold War era, missile defense is still a thorny question in Russia-US relations," 后冷战时期，导弹防御仍然是美俄关系中的棘手议题。 "The super-committee failed to reach an agreement on the thorny deficit problem," 美国超级委员会没能就棘手的赤字问题达成一致。好的，今天我们学习的词是thorny...