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their colours are blue and black is the most popular phrase on the web.

their colour is blue and black 10 results on the web	their colours are blue and black 13 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	... competition during the 2008/09 season. Central City's home ground is Bob Jane Stadium. The club kit supplier is Legea, and their colours are blue and black. ... for the House of Udatos are: perseverance, persistence, adaptability, power, goodness. Their animal is the orca whale, and their colours are blue and black. ... various kinds of crime, particularly drug dealing. Its symbol is the clenched fist of the American black power movement, and their colours are blue and black.

their colour is blue and black

10 results on the web

their colours are blue and black

13 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

... competition during the 2008/09 season. Central City's home ground is Bob Jane Stadium. The club kit supplier is Legea, and their colours are blue and black.
... for the House of Udatos are: perseverance, persistence, adaptability, power, goodness. Their animal is the orca whale, and their colours are blue and black.
... various kinds of crime, particularly drug dealing. Its symbol is the clenched fist of the American black power movement, and their colours are blue and black.