Despite Mr. McDonald's success in staying off drugs, financial demands still strain the family, he said.
The heavy demand for PlayStations has strained some online retailers.
Within three years, the demands of printing 28,000 copies a day were straining the operation to the breaking point.
Her children still needed dinner and attention, and their constant demands strained her nerves.
The Big Three's problem is not simply too much demand for factories strained to capacity, however.
New demand has recently strained supply, and there is growing concern that the world may soon face a shortage of the rare earths.
And their demand for foreign currency has strained the Soviet Union's hard-currency resources.
Mr. Jones said excessive demand could strain pumps and reduce water pressure - an annoyance for customers, but a potential crisis in a fire.
Prosecutors say the demand is straining their resources, forcing them to spend more than triple the amount of five years ago.
With grasslands, the other natural system on which we depend heavily for animal protein, demands are also straining the limits on every continent.