This works because gravity holds you firmly on the ground, and your feet stay put because of friction with the floor.

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But while this works in Latvia, a relatively marketised economy, in Greece there is a lot of friction - and not just because of organised labour resistance.

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But if one person's mind was changed because of her actions, Foster said it was worth the nerves and friction.

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For every company that fails for business reasons, ten more fail because like so many rock bands, they are overwhelmed by the friction of conflicting agendas, personal animosities, and pervasive mistrust.

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My wife, who was born in Guadalajara and came to the United States legally as a child, reminds me that there is friction between Mexicans and Mexican-Americans because Mexicans have a firmer grasp of who they are and Mexican-Americans resent that.

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This friction has emboldened those Russians who would prefer to stay out, either because they dislike the idea of Russia joining anything, or because they fear for vulnerable sectors, such as agriculture: Russian produce will struggle to compete with subsidised European fare.

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