13. An apparatus, comprising: a processor; and a memory coupled to the processor and storing first data representing a semantic network, the semantic network representing a plurality of nodes, and a plurality of links interconnecting the nodes such that, for each of the links, one of the nodes is a subject node of the link, another of the nodes a target node of the link, and the respective link represents a verb between the corresponding subject and target nodes, at least some of the links each being conditioned by at least one variant, wherein the processor is configured to, in response to receiving second data representing one or more variants: determine a portion of the semantic network that contains fewer links than the semantic network depending upon which of the variants are included in the second data and which of the variants condition the at least some of the links, and generate third data based on the determined portion of the semantic network.
17. The apparatus of claim 13 , wherein the semantic network further comprises a further link having one of the plurality of links as a subject or target of the further link.