Modal verbs and be going to

 

COULD 

Could is a modal verb used to express ability, possibility or to ask permission. Could functions as an auxiliary verb, therefore, it must always be placed before the main verb of the sentence so that it conditions it.

When is the verb could used? 

We use could to express that something is possible or the probability of something happening, for example:

Affirmative form: 

Subject + could + infinitive verb.

Example: 

It could be really nice to go to a movie together on the weekend.

She could arrive later from her trip.

Negative form:

Subject + could + not + infinitive verb.

Example: 

I could not have arrived earlier, I was too inconvenienced.

Or to ask permission in a more polite and formal way

Interrogative form:

Could + subject + infinitive verb. 

Example:

Could you help me clean things up? 

Could I keep your history book for the week?

wh-questions 

Where could I find that information? 

On the website 

SHOULD 

How is the verb should used? 

It is used after any personal pronoun and followed by an infinitive verb, using the following structure:

Affirmative :

Subject + should + infinitive verb.

Example: 

You should visit the doctor so that she can prescribe the correct medications for you.

Negative :

Subject+verb should + not+ infinitive verb.

Example:

You should not eat things that are so harmful to your body. 

Interrogative :

Subject + should + infinitive verb. 

Example: 

Should you start going to the gym?

wh-questions: 

example: when should i call my mom? 

BE GOING TO 

The verb going to is used to refer to future plans that have already been decided.

 Affirmative:

Subject + verb to be + going to + base form.

Example: 

I am going to the movies with Andrea and Sofia. 

Negative: 

Subject + verb to be + not + going to + base form.

Example: 

She isn't going to study for the exam. 

Interrogative:

Verb to be + Subject + going to + base form? 

Example:

Are you going to go to the movies with us?

Hello baker travel, can I help you?

Yes I'm going to need a car In Barranquilla for two weeks

Perfect, it's not a problem, 

what are you arraving?

November ten 

Ok what Time?

Six o'clock PM.... Mmm AND going to need other services please

Yes off course, what other ?

I need five express tickets for november eleven 

Yes, ok that's no problem, I can deliver them on the day of their arrival