2.224 PRODUCTIVE FEATURE

Whenever you want to talk about a limited amount of something, to indicate the area that something occupies, or to specify a particular feature that it has, you can use a noun group which indicates the amount or the nature of the thing linked by 'of' to a noun group which indicates what the thing is. For example, if you say 'a forest of pines', you are talking about a large area of trees. Similarly, you can talk about 'a border of roses'. This structure can be extended very widely, so that you can talk about 'a city of dreaming spires' for example. This is one of the most productive features of English. Productive features are explained in the Introduction.