Particles are not as important in English as they are in Thai, Cambodian, Indonesian, Tagalog, in short all the languages of south-east Asia. They also exist in NE Asian languages.
English equivalents are for example:
If you study any of these languages, verbs are generally not conjugated, there are no tenses and so important notions like time and continuity are left up to adverbs and particles.
List of Thai Particles
List of Mandarin Particles
List of Malay Particles
List of Japanese Particles