It may be presumed to be a necessary ingredient in onerosity, that the obligation to be fulfilled is a legal one.

[T]he very wet winter will have washed much of the goodness out of the soil. Homemade compost and the load of manure we get from a friendly farmer may not be enough to compensate for what has leached from the ground.

In trying to understand the ideal theory of a commutative ring, one quickly sees that it is important to first understand the prime ideals.

The empty space at the sides of the page is called the margin.