Aspectual classes

Aspectual classes is a term that used for a classification of verbs with respect to their aspectual properties, dating back to an Aristotelian classification of situations.

Examples
(i)  States: ''Socrates is mortal. She is in danger. He loves potatoes.'' (ii) Activities: ''John walked miles and miles. She drove him safely.'' (iii) Accomplishments: John walked home, She ate a sandwich. (iv) Achievements: ''She reached the top. He won the race.''

Comments
The most popular aspectual classes are those proposed in Vendler (1967) (extending a classification in Kenny (1963)) and applied and formalized in Dowty (1979): States, Activities (unbounded processes), Accomplishments (bounded processes), and Achievements (point events).

Linguistically, the classification is often used for the analysis of aspect. However, Verkuyl (1989,1993) argues that aspectual classes have no explanatory function in the analysis of aspect. For him, the opposition between States and Activities on the one hand and Accomplishments and Achievements on the other hand is considered central, also known as the contrast between durative/atelic aspect versus terminative/telic aspect. Durative sentences, but not terminative sentences can be used with a durative adverbial like for hours:

(v)  For hours she was in danger.

(vi) ?For hours she reached the top

Sentence (vi) can only be interpreted with a repetition, indicating that She reached the top is a terminative sentence. In Slavic languages, terminative aspect can be morphologically marked.

Link
Utrecht Lexicon of Linguistics