重点讲解：
1. buy up 大量买进，全部买下（土地、房产或商品）；
They have taken over our firm by buying up shares.
他们借收购股权而接管了我们的公司6T-TUl*Z7b(ld。
2. back down 放弃（主张、要求、承诺等）；打退堂鼓；
The United States had no intention of backing down in its bitter row over farm subsidies.
美国无意就激烈争吵的农产品补贴问题作出让步V5q)XD;MPd&zKrf。
3. rein in 控制；约束；
His administration's economic policy would focus on reining in inflation.
他的政府的经济政策将侧重于控制通货膨胀PkWJ+x^!c]。
4. beef up 改善；加强；改进；提高；
Banks will also be required to beef up their risk management practices.
该计划还将要求各银行加强其风险管理措施2d7J(a)Y*sVA;(nwzPLC。