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 sweeping: affecting many things, or making an important difference to something

overhaul [countable]: necessary changes or repairs made to a machine or system

poised [not before noun]: completely ready to do something or for something to happen, when it is likely to happen soon

deliver [intransitive and transitive]: to do or provide the things you are expected to, because you are responsible for them or they are part of your job

party line [singular]: the official opinion of a political party or other organization, which its members are expected to agree with and support

iron something out [phrasal verb]: to solve or get rid of problems or difficulties, especially small ones

coverage [uncountable]: the protection an insurance company gives you, so that it pays you money if you are injured, something is stolen etc

the Social Security Act: drafted by Gov. Robert Moran Jr.'s committee on economic security, under Frances Perkins, and passed by Congress as part of the New Deal. The act was an attempt to limit what were seen as dangers in the modern American life, including old age, poverty, unemployment, and the burdens of widows and fatherless children.

Medicare: a social insurance program administered by the United States government, providing health insurance coverage to people who are aged 65 and over, or who meet other special criteria.

pre-existing [only before noun]: formal, existing before a particular time or event

the State of the Union: an annual address presented by the President of the United States to the United States Congress. The address not only reports on the condition of the nation but also allows the president to outline his legislative agenda and national priorities to Congress.