回复: overuse,underuse计算
You can use WordSmith to make "wordlists" of word clusters (i.e. two-word, three-word clusters etc). But since you are considering both single words and phrases, wordsmith will find the task difficult.
You can try Wmatrix at Lancaster, which tags both words and phrases grammatically and semantically and also provides a utility to compute keyness. Registration is free for a month and if you want to continue to use it after that, an annual fee is applicable.