In english grammar, modal auxiliary verbs are used to express modality. In language, modality is a term by which possible situation is explained by speaker in terms of positive or negative degree of possibility to obligation. Modal auxiliary verbs are originated out of these and classified to function as per situation. Here, I’m going to explain can and may modal auxiliary verbs differences.
Difference between Can and may modal auxiliary verbs
Can and may modal verbs often used interchangeably. Sometimes they overlap each other while expressing moods of ability, possibility. But there is small difference in case of asking or giving permission, expressing wish. Here on, we are going to discuss them one by one.
Simply all modal verbs express modality like possibility, permission, obligation, and ability in negative or positive way.
But, modal verbs do not conjugate as per the tense and person like primary auxiliaries.
Functions of can and may modal auxiliaries.
To express ability, possibility, and permission, “Can” modal auxiliary is used. On the other hand, to express stronger permission, factual possibility, and wish “may” modal plays important role.
Use of “can” modal verbs to express ability
- It can deliver your pizza order within 10 minutes.
- She can judge a person in first glance.
- Our students can solve word puzzles in few seconds.
- This new car can catch the top speed in fraction of a second.
- Alex can design website anyways.
- Swimming in the sea water is a herculean task for me but not for my brother Max. He can swim in any waters.
- Really, he is a master rider, as he can ride safely through the crowded roads.
Here, can deliver, can judge, can solve, can catch, can design, can swim, can ride are abilities shown by “Can” modal.
Most importantly, modal verbs do not conjugate like primary auxiliaries, nor take conjugated forms of main verbs but just transfer the meaning of main verbs.
In the above examples, deliver, judge, solve, catch, design, swim, ride are main verbs without conjugated forms. Conjugated forms are nothing but those verbs changed accordingly number, person and tense.
Theoretical vs factual possibility
The river water can damage bridge. (It is not damaged yet, and there is evidence to happen so)
Oh! The river water is crossing danger mark, and it is possible that it may damage bridge soon.
“Can” modal auxiliary verb is used to express theoretical possibility, whereas “may” modal expresses factual possibility.
Stronger Vs weaker and formal Vs informal permission
Permission includes both to ask for or to grant somebody.
- Your duty is over. Now, you can go.
- Do you know that you are too late? So, you can’t continue.
- Sir, I have submitted my application. Can I go now?
- Ok. My work is done. He may go now.
- She cannot leave without completing his job.
- I know how to make drawing. May I help you?
“May” modal auxiliary verb is more preferred in terms of permission than “Can”. It is stronger and more formal compare to “Can”.
“May” is used as more formal word compared to “can” in daily conversations.
May modal verb for expressing wish or hope
Expression of wish is an another ground on which Can and may modal auxiliary verbs differ from each other. Expression of wish sounds good with the use of “may” modal verb. But on the other hand, when we use can not use “can” modal verb to express wish.
Examples of may modal verb to express wish and hope
- May his soul rest in peace.
- I think he may find some respite after this verdict.
- You have just married. May you have a happy married life.
So, in day-to-day interactions, “may” modal verb is more preferred to “can”. In the next blog, I will bring another modal verb for discussion.