League and union
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two teams of 15 players
four. two in the front. two in the back
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The two main categories are convenience goods and shopping goods; two lesser categories are specialty items and unsought goods.
Deoxyribose and Ribose
descriptive and inferential
botany and zoology.
IT is separated into two main categories (1) those which process information, such as computer systems, and (2) those which disseminate information, such as telecommunication systems.
Most famous would be Jonah Lomu and Jonny Wilkinson
animal and vegetable
linear and non-linear resistor