The rules of the single currency expressly forbid any bail-out of one country by the centre or by other countries.

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Many modern contracts expressly forbid the consumption of alcohol.

ECONOMIST: Drinking at work: The boredom of boozeless business | The

Marijuana use laws in Arizona, Connecticut, Delaware, Maine, and Rhode Island expressly forbid businesses from refusing to hire applicants and from disciplining and otherwise adversely affecting the employment of registered medical marijuana card holders based solely on that status.

FORBES: 'What Were They Smoking?' States' Legalizing of Marijuana Means Headaches for Employers