1. A computer-implemented method, comprising: obtaining, with a processing device, a set of candidate concepts of a surface form in a sequence of surface forms in a plaintext; determining first probabilities for the candidate concepts, a first probability indicating likelihood that the surface form represents the respective candidate concept; and selecting one of the candidate concepts for the surface form based on the first probabilities and adjacency of the surface forms in the sequence, wherein selecting one of the candidate concepts for the surface form based on the first probabilities and adjacency of the surface forms in the sequence comprises: determining occurrence probabilities for the candidate concepts based on the first probabilities and the adjacency of the surface forms in the sequence, an occurrence probability indicating likelihood that the respective candidate concept is mentioned in the plaintext; and selecting one of the candidate concepts for the surface form based on the occurrence probabilities.