Exercise：Complete the sentences with the words from the box.breakthrough dropout comebackthrowback drawback1.The company is now using innovative financing strategies to achieve ____________ of its business the newly launched mobile chatting app is convenient and fast.2.She’s trying to make a_________ with her first album for 20 years.3.He was a high-school_________ but was eagerforknowledge.4.Perhaps the biggest__________of onlinesocial networking is that it makes identity theft easier.5.Her whole outfit was a ____________ to the 1970s