Course paper on theoretical grammar

The opposite of dynamic verbs of action is stative verbs of being. Stative verbs describe a subject’s state or feeling, including things they like and don’t like. 

Examples: want, need, prefer, love, hate, like, dislike, seem, understand, know, believe, involve, realize
One of the most important parts of stative verbs is that you can’t use them in the continuous tenses. Stative verbs stick to the simple tenses, or occasionally use the perfect. 
The trouble is that some verbs can be dynamic or stative, depending on the specific meaning and how they’re used. This includes the most popular verb be. Let’s take a deeper look at these.
Verbs that can be dynamic or stative. A lot of verbs have more than one meaning, so they can be used as dynamic or stative. These include perception words: see, hear, taste, smell, feel. 
When perception verbs are used as an involuntary action, such as passive or unintentional actions, they are stative. This applies when these verbs are used in the general sense, a state of being that’s always happening. 
I can’t see without my glasses. 
Cake still tastes great even if it’s not your birthday.
When those same verbs are used for a voluntary action—specific, deliberate, and/or temporary events—they are dynamic. Among other things, it means they can be used in the continuous tenses. 
I haven’t been seeing well since I lost my glasses. 
We were tasting cakes for the wedding all afternoon. 
Likewise, some perception verbs have alternative meanings, especially if they’re part of expressions or phrasal verbs. Often, this means they act as dynamic verbs. 
Romeo and Juliet had been seeing each other for just five days when they died. 
Other verbs, like think, have, and, above all be, follow the same voluntary/involuntaryrules as perception verbs. Depending on how they’re used, they can be either dynamic or stative. 
I think toads are better than frogs. 
(stative: expresses an opinion or feeling always there; involuntary)
All morning I was thinking about how toads are better than frogs. 
(dynamic: expresses the temporary action of thinking; voluntary)
I have a ten-year-old dog. 
(stative: expresses permanent ownership; involuntary)
I am having a party for my dog’s eleventh birthday. 
(dynamic: used as part of phrase; voluntary)
He is nice to everyone. 
(stative: expresses an ongoing state or personality trait; involuntary)
He was just being nice to everyone to get a promotion. 
(dynamic: expresses a temporary/intentional state; voluntary)

Auxiliary (helping) verbs

Auxiliary verbs, or “helping verbs,” are used in English to change another verb’s tense, voice, or mood. When auxiliary verbs are used, there’s always a main verb that represents the main action. However, the auxiliary verb must still be conjugated correctly. The main auxiliary verbs are be, have, and do. We explain how they’re used specifically for conjugating below, but here are a few quick examples: 

I have eaten sushi many times before. (tense)
That piece of sushi was eaten by me. (voice)
Did you eat my sushi? (mood)

Modal auxiliary verbs

Some auxiliary verbs are added to another verb to show necessity, possibility, or capability. Like other auxiliary verbs, modal auxiliary verbs are not the main verb, but they do change its meaning slightly. Some common examples are can, may, could, should, would, must, ought, and might.
I could swim across the English Channel, but should I do it? 
She must be the strongest person on the team, and might be the strongest person in the region.