Rego says that because a bad mood rarely has a single cause, there is no single treatment.

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These events are widely advertised and rarely have even a single security guard or police officer.

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People rarely act with a single purpose in mind.

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It's hard to imagine where these airlines would park or operate, since the airport has only one runway, a single luggage carousel that rarely runs and no PA system.

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Single-element mirrors rarely exceed eight metres in diameter.

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The dominance of employer-sponsored insurance (ESI) was solidified in an era of single income households where the breadwinner rarely changed jobs.

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Successful entrepreneurship rarely happens within the confines of a year, let alone a single semester, and our half-hearted attempts at starting businesses every semester (only to let them die at winter and summer breaks) reinforced a misleading expectation: that success can be validated quickly.

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They have not gained business: tellers are under pressure to serve a queue rather than chatting to a single customer, and in any case the appropriate salespeople are rarely at the ready.

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The insurgency is not a single-headed beast, but rather a loose affiliation of many different groups that rarely act in a coordinated way.

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