What is an Activator? Like thesauruses, Longman Activators? help students develop their vocabulary by taking them from key words and basic ideas and guiding them to exactly the right word or phrase they need for a particular context or situation - guaranteeing natural sounding English. Includes 42,000 words, phrases and examples. The CD-ROM guides students through all stages of writing an essay, with practice and samples and also includes the full contents of the Longman Active Study Dictionary.