WELCOME TO MY BLOG: Function, Difference , and Example of "Can, Could and Be Able to", "Must and Has/Have/Had To", "Will,Would , and (be) Going To", "Shall, Should and Ought To"

CAN, COULD VS BE ABLE TO

There is generally quite a bit of confusion amongst English learners about the difference between and the usage of CAN and BE ABLE TO, I will try to clear that up by explaining the difference in simplified terms. If it still doesn’t make sense, then hopefully the example sentences will help!

CAN and BE ABLE TO are often interchangeable and you can usually use either one without a difference in meaning, but sometimes you cannot.

The difference in grammatical terms is:

Ø CAN is a modal auxiliary verb that expresses general ability to do things in the Present tense,

Ø COULD ,same with CAN but this modal can be used to express in the Past tense.

Ø BE ABLE TO can also be used to express general ability, although it sounds a bit more formal.

BE ABLE TO is not a modal auxiliary verb. it is a combination of the verb ‘BE’ + the adverb ‘ABLE’ + the infinitive ‘TO’. BE ABLE TO can also be used to express general ability, although it sounds a bit more formal.

Example :

CAN :

- He can drive safety in the rain

- you can come to my house

COULD :

- I couldn’t finish all my homework yesterday

- Before my accident, I could run faster than everyone in my school

ABLE TO :

- I’m able to work independently and in a team

- Michelle is able to bake delicious cakes.

MUST Vs HAVE/HAS/HAD TO

“Have to” and “must” are very similar in meaning , we use it depends on whether we want to express obligation or if we want to say how certain we are about the probability of something happening.

Must means "really should or else it will be bad for you", it expresses an obligation forced by the speaker.

Have / Has to expresses general obligations. When we are talking about another person's obligation we use have to, too. We use have to when the obligation comes from outside. Let us Compare:

I have to stop smoking. (Doctor's orders)

I must stop smoking. (I want to.)

And for the difference between Have , Has and Had, Have is used for some plural noun and pronoun, Has is used for singular noun and, Had can be used for Past tense.

Example

Must :

- - I must come to school on time tomorrow

- - I must stop smoking from now

Have/has/had to:

- - They have to wake up early in the morning

- - She has to buy new dictionary for school

Will, Would Vs (be) Going to

Will (future simple) is used to express future intentions that are decides at the time of speaking (spontaneous offers, promises and decisions). And we can used would for past future

Be going to is used to express future intention that have already been decided before the time of speaking

Example :

Will

- - I will help you with those books

- - will you accept my apology?

Would

- - If I were a millionaire, I would donate my money to charity

- - Would you mind to help me?

Be going to

- - My sister is going to have a baby

- - We are going to get married

Shall,should Vs Ought to

The basic difference between “shall” and “should” is that “should” is the past tense of “shall.” But when we use these words or modals, the usage is not as simple as using “should” in place of “shall” in the past tense.

“Should” is used as deontic modal as well as epistemic modal. Modals are helping verbs. They are also called modal auxiliary. They have varied meanings and are used to convey these varied meanings. “Should” is specifically used to express advisability. Deontic modals are verbs which are used to give permission and, hence, affect a particular situation. Epistemic modals are verbs which show the opinion of the one who is speaking.

Shall has slightly different usages and meanings. “Shall” means something that is intended to take place in the future. It mainly used in American English to ask question politely. For the nfuture tense, will is more frequently used in American English than shall. It often used in formal setting to deliver obligation or requirement.

Ought to is a semi-modal verb because it is in some ways like a modal verb and in the some ways like a main verb. We use ought to when talking about things which are desired or ideal. Ought to and should are similar in meaning. Should is more common than ought to. Ought to is more formal than should.

Example:

Shall