There are some verbs in English that do not normally occur with progressive aspect, even in those contexts in which the majority of verbs necessarily take the progressive form. Among the so-called ‘non-progressive’ verbs are think, understand, know, hate, love, see, taste, feel, possess, own, etc. The most striking characteristic that they have in common is the fact that they are ‘stative’ - they refer to a state of affairs, rather than to an action, event or process.