【正确答案】正确答案：The most important use that we can make of corpora is that we can find very useful information about how language is actually used. Corpora usually provide a few types of information, and these types of information are helpful to our lexical studies. (1) Frequency information. Corpora can tell us how frequently certain language items or structures are used. This kind of information is useful when we try to select what to focus on, and decide what senses to focus on in lexical study. (2) Context and co-text information. Contexts are the situational environments in which language is used. Co-texts are the linguistic environments. Sometimes it is very difficult to tell the differences of two words or phrases which have similar meaning. However, if we look at the context and co-text in which they are used, the difference becomes clear. (3) Grammatical information. We usually refer to grammar books for grammatical information. However, what the corpora show is far more complicated than what grammar books tell about grammar. It helps to grasp lexical in a grammatical way. (4) Collocation and phraseology information. It is usually difficult for second and foreign language learners to learn which words are frequently used together, e. g. should we say make effort or take effort? A search in corpus will do the job. It's quick and efficient. (5) Pragmatics information. Information from corpora can tell us how language is actually used in communication. For example, "Watergate" is used to indicate President Nixon's political scandal.