It can be put in present perfect and past perfect using "if" like this: If the train have already left , we shall/will take the next train. (formal present perfect subjunctive) If the train had already left , we should/would

There are none. The modals have no past participle, and there is no verb construction in English requiring them.

I find that have to is most often called a semi-modal . It has the effect of a modal like must , but is conjugated like an ordinary verb. ( has to, have to, had to, ... ) I would certainly not call it an auxiliary verb with an infinitive, though

The reason I made that comment was already explained. I thought your English level was better than to ask the elementary questions on modals. That's all, nothing derogatory. Hey, it's absolutely no problem at all...but the ironic thing

Without your second post asking "how come", I was so sure that you meant "the modal rules". The reason I made that comment was already explained. I thought your English level was better than to ask the elementary

Hi pleasehelp In your sentence, "have been" is what is known as a perfect infinitive . There are some other threads here that discuss perfect infinitives. Here are a few of them:

I still have trouble with this kind of construction s , You cannot have would had . Impossible. The only form of have which can directly follow a modal verb is have , never has, had, or having . These are the correct combinations: can have,

What is your favourite Grammar Book? I'm pleased you like my explanation! Thank you for that. I don't really have a favourite grammar book - and I haven't read a grammar book for about 30 years anyway. I think for basic elementary

As a rule of thumb, use the infinitive after an adjectiv e: It's i mpossible to do that. It's easy to learn foreign languages. It may be difficult to win the match. It is true that the gerund is used in some cases instead of the

Thank you. You wrote/corrected (with your comment): 2. This seminar could prove beneficial to those who haven't attended a school in the past. -- In the right context you could say this but as a standalone sentence the article