Exercise 4: Cross out the extra word.

Analysis of Categories:

• Countries: England, Wales, Scotland, Northern Ireland.
• Rivers: Thames, Severn, Tweed, Clyde.
• Cities: London, Sheffield, Belfast, Edinburgh, Washington.
• Authors/Writers: William Shakespeare, Robert Stevenson, Mark Twain.
• Landmarks/Places: Stonehenge, Westminster, Windsor Castle, Trafalgar Square.
• People (likely entertainers/sports): Daniel Armstrong, Elton John, Michael Jackson, David Bowie.

Step-by-step identification:

• Line 1: England, Wales, America, Scotland, Northern Ireland. 'America' is a continent/country, while the others are countries within the UK. If the context is UK, 'America' is extra.
• Line 2: Thames, Severn, Tweed, Clyde, Nile. All are rivers, but 'Nile' is geographically outside of the UK/Europe context implied by the others. If the context is UK rivers, 'Nile' is extra.
• Line 3: London, Sheffield, Belfast, Edinburgh, Washington. All are cities. 'Washington' is in the USA, while the others are in the UK. If the context is UK cities, 'Washington' is extra.
• Line 4: William Shakespeare, Robert Stevenson, Mark Twain. All are famous authors.
• Line 5: Stonehenge, Westminster, Windsor Castle, Trafalgar Square. All are famous landmarks/places in the UK.
• Line 6: Daniel Armstrong, Elton John, Michael Jackson, David Bowie. These are all famous individuals, likely from entertainment or sports.

Crossed out words:

• Line 1: America (assuming UK context)
• Line 2: Nile (assuming UK rivers context)
• Line 3: Washington (assuming UK cities context)
• Line 4: (No extra word, all are authors)
• Line 5: (No extra word, all are landmarks)
• Line 6: (No extra word, all are famous individuals)

Note: The identification of the 'extra' word depends heavily on the intended grouping for each line. If a different context is assumed (e.g., all are geographical locations), then 'William Shakespeare' etc. might be considered extra.