Questions

Error is in second part. Returning means coming back to place from where you began. So, the use of back after returned becomes redundant. Without using back, the meaning remains the same. We can omit ‘back’ in part b, and use ‘returned home.’

Error is in second part. Replace ‘grave’ with ‘graver’. Since problems are being compared in the given sentence we will use the comparative form of ‘grave’ that is ‘graver’.

•SWIFT was founded in the 1970s, based on the ambitious and innovative vision of creating a global financial messaging service, and a common language for international financial messaging.

•The Uruguay Round was the 8th round of multilateral trade negotiations (MTN) conducted within the framework of the General Agreement on Tariffs and Trade (GATT), spanning from 1986 to 1994 and embracing 123 countries as "contracting parties".

•The World Trade Organization (WTO) is an intergovernmental organization that regulates international trade. The WTO officially commenced on 1 January 1995 under the Marrakesh Agreement.

•Founded by the National Association of Securities Dealers, the NASDAQ began trading on February 8, 1971, as the world's first electronic stock market.