The modal verbs are:

can could
may might
shall should
will would

We use modal verbs to show if we believe something is certain, probable or possible (or not). We also use modals to do things like talking about ability, asking permission making requests and offers, and so on.



The Taj Mahal complex is believed to have been completed in its entirety in 1653.
so, the structure "is + 3rd form of the verb + to+ have been" what the meaning of this.

and second thing is:

May have +3rd form of the verb
might have + 3rd form of the verb
May have been + 1st form of the verb + ing
might have been + 1st form of the verb + ing
would have + 3rd form of the verb
would have been + 1st form of the verb + ing

supposed to have been
seems to have been

give me the proper use of above

Hello RV,

I'm afraid we don't provide on-demand explanations of multiple questions that would take quite a bit of time to answer properly. Rather, what you are welcome to do is review our pages and then ask us a question about something on one of our pages. Occasionally we also answer questions that are related to what's on our pages, but these questions must be specific.

So I will take your first question and try to help you with that one. First of all, note that this is a kind of passive voice structure with an infinitive. You could rephrase your passive voice sentence to something like 'Historians believe the Taj Mahal complex was completed in its entirety in 1653.' If, for whatever reason, you don't want to mention the historians, you can transform it into the sentence you ask about by changing 'believe' into the passive and 'was completed' into a passive perfect infinitive ('to have been completed' -- the active form of this perfect infinitive would be 'to have completed', but that doesn't work here).

By the way, for explanations that might help you understand the other forms you ask about, read further in this Modal verbs section and you should find some useful content.

All the best,
The LearnEnglish Team

I wanna know the uses of continuous (modal+be+ing) and perfect continuous (modal+have been+ing) of modal verbs.

Hello jodu23,

The use of modal verbs varies a great deal according to context - the same modal verb can have many meanings and each meaning can be expressed by several different verbs. We can't really provide long explanations of all the different possibilities in the comments sections here so I will comment on one particular example.


  1. John must be working.
  2. John must have been working.

In the first sentence the speaker is making a guess about the present - that John is in the process of doing.​ We can express the same sense by John is likely in the middle of his work right now.

In the second sentence the speaker is making a guess about the past. We can imagine that the speaker has some evidence (John is looking tired) and is speculating about the cause of this.


Best wishes,


The LearnEnglish Team

You have made me clear. I want to study this in details. Could you give me a reference or source where I will find it in details??

Hello jodu23,

I'm glad we could help. The British Council doesn't recommend other sites because they tend to be commercial in one way or another. Your examples are modals of deduction and a search for these (present and past) would be a good place to start.


Best wishes,


The LearnEnglish Team

Thank you very much.

hello team
please can you show a way to modify was, were (continuous tenses) and and past tense
using should, must etc.
eg. Her body was found near the school, she must was going to school.

Hello raj jk,

'must' and other modal verbs can not be followed by a finite verb like 'was going'. They can only be followed by some form of infinitive. In this case, I'd suggest the perfect continuous infinitive: 'must have been going'.

All the best,
The LearnEnglish Team

Sir, As we use the model verb 'Shall' For request and offer like-
"Shall I take your Moterbike for today ?" and
"Shall I hold it for you ?" But If I have to speak somthing to someone orderly like- Like someone calls me on my phone at 2"0" Clock at night and Now I want to speak him forcefully or orderly, then Could use "Will" rather than Shall like- "Will we talk tomorrow" For giving order, Because I think we can't use "Shall" For giving orders. So Sir, Could use will like this please explain and could we also use 'Will' Like Shall as above ?