Modals of Possibility and Probability for Past Situations. Must, may, might, can’t and couldn’t are used with a present perfect verb form to show how certain a speaker is that a past situation happened or didn’t happen.

he modals are used to show that we believe something is certain, probable or possible:

Possibility:

We use the modals could, might and may to show that something is possible in the future, but not certain:

They might come later. (= Perhaps/Maybe they will come later.)

They may come by car. (= Perhaps/Maybe they will come by car.)

If we don’t hurry we could be late. (= Perhaps/Maybe we will be late)

We use could have, might have and may have to show that something was possible now or at some time in the past:

It’s ten o’clock. They might have arrived now.

They could have arrived hours ago.

We use the modal can to make general statements about what is possible:

It can be very cold in winter. (= It is sometimes very cold in winter)

You can easily lose your way in the dark. (= People often lose their way in the dark)

We use the modal could as the past tense of can:

It could be very cold in winter. (= Sometimes it was very cold in winter.)

You could lose your way in the dark. (= People often lost their way in the dark)

Impossibility:

We use the negative can’t or cannot to show that something is impossible:

That can’t be true.

You cannot be serious.

We use couldn’t/could not to talk about the past:

We knew it could not be true.

He was obviously joking. He could not be serious.

Probability:

We use the modal must to show we are sure something to be true and we have reasons for our belief:

It’s getting dark. It must be quite late.

You haven’t eaten all day. You must be hungry.

We use must have for the past:

They hadn’t eaten all day. They must have been hungry.

You look happy. You must have heard the good news.

We use the modal should to suggest that something is true or will be true in the future, and to show you have reasons for your suggestion:

Ask Miranda. She should know.

It’s nearly six o’clock. They should arrive soon.

We use should have to talk about the past:

It’s nearly eleven o’clock. They should have arrived by now.

The present perfect continuous (also called present perfect progressive) is a verb tense which is used to show that an action started in the past and has continued up to the present moment. The present perfect continuous usually emphasizes duration, or the amount of time that an action has been taking place. Read on for detailed descriptions, examples, and present perfect continuous exercises.

Have you been waiting here for two hours?

The present perfect is a verb tense which is used to show that an action has taken place once or many times before now. The present perfect is most frequently used to talk about experiences or changes that have taken place, but there are other less common uses as well. Read on for detailed descriptions, examples, and present perfect exercises.

You have seen that movie many times.

A preposition is an official part of speech which expresses the relationship between the subject and the object in a sentence. In English, prepositions are usually used with nouns and pronouns, but they are also used with verbs.

In / Into

The key difference between ‘in’ and ‘into’ is that ‘in’ indicates a state of being, whereas ‘into’ indicates motion. For example, ‘into’ is often used to describe the movement of something from outdoors to indoors, such as in the sentence, «I walked into the house.» By contrast, ‘in’ is used when a thing or person is stationary. For example, «I found the book in the drawer.»

Examples

Jack drove his car into the garage.

My friend lives in that house.

The teacher came quickly into the room and began the lesson.

The dishes are in that cupboard.

On / Onto

Similar to ‘into’ and ‘in’, ‘onto’ indicates motion where ‘on’ does not. ‘Onto’ normally indicates that something is placed onto something else. For example, «I put the dishes onto the table when I set it.» ‘On’ shows that something already rests on a surface. For example, «The picture is hanging on the wall.»

Examples

I carefully placed the picture onto the wall.

He put the book onto the desk.

You can find the dictionary on the table.

That’s a beautiful picture on the wall.

Among / Between

‘Among’ and ‘between’ are almost exactly the same in meaning. However, ‘between’ is used when something is placed between two objects. ‘Among’, on the other hand, is used when something is placed among many objects.

Examples

Tom is between Mary and Helen in that picture.

You’ll find the letter among the papers on the table.

Seattle is located between Vancouver, Canada, and Portland, Oregon.

Alice is among friends this weekend.

Beside / Besides

‘Beside’ – without an s- means ‘next to’. For example, «Tom is seated beside Alice.» In contrast, ‘Besides’ – with an ‘s’ – states that something is in addition to something else. For example, «Besides math, Peter is getting an A in history.»

Examples

Hang your coat beside mine over there.

There is so much work to do besides the normal tasks.

Come sit down beside me.

Besides potatoes, we need some milk.

There are two modal verbs for advice: should and would. You can see how to give advice with the lesson below. The exercises are at the bottom of the page.

 You should eat healthy food.

You should exercise every day.

Gerunds

the gerund is a common part of speech that most of us use every day, whether we know it or not. Here, we’ll take an in-depth look at gerunds and provide you with several examples of gerunds so you’ll feel comfortable using them in your writing, and so that you will be able to recognize them when you see them.

Let’s go dancing at the club tonight

Infinitives

Modal verbs are auxiliary verbs (also called helping verbs) like can, will, could, shall, must, would, might, and should. … When a modal verb precedes the main verb in a sentence or clause, use the root of the verb rather than the infinitive, which contains the word to.

You must turn in your assignment on time.

He might be the love of my life.

The doctor can see you now.

The simplest definition of an adjective is that it is a word that describes or clarifies a noun. Adjectives describe nouns by giving some information about an object’s size, shape, age, color, origin or material.

It’s a big table. (size)

It’s a round table. (shape)

Modal of Impossibility. Modal verbs, can’t and couldn’t are used to express impossibility or disbelief.

My neighbor couldn’t be at the door as he is not in the town.