Author Topic: Still baffled when to use “can” or “could” and “will” or “would”?  (Read 7655 times)

Joe Carillo

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I think it’s high time for a full review of the choice between the function words “can” and “could,” “will” and “would,” and also “shall” and “should.” From my experience as an editor, they continue to be frequent pitfalls to many English learners and even some long-time writers in English.

The most important thing to remember about these word-pairs is that they aren’t meant for conveying simple facts or absolute certainties. They are distinct grammatical forms called modal auxiliaries or modals, and they work in tandem with a given verb to convey varying shades of necessity, advice, ability, expectation, permission, possibility, or conditionality.

“Can” or “could.” These two modals convey the idea of ability, possibility, permission, or potential to perform an action or do a task—“can” is the present-tense form, and “could” the past-tense form. Use “can” to convey a current ability, as in “As a single woman I can write novels,” but use “could not” when that ability has been lost, as in “As a mom of three hyperactive toddlers I could not write novels anymore.” Use “can” to convey possibility: “The team can win if its members are more disciplined.” Use “can” to ask permission: “Can I go out with my playmates now?” And use “can” to indicate potential: “With his political acumen, he can be presidential timber.”

The modal “could” likewise conveys a deferential or polite request, offer, or suggestion: “Could you tell me how to leave the send-off party now without offending the boss?” But among social, age, or professional coequals, “can” is more suitable without raising eyebrows: “Can you tell me how to leave the send-off party now without offending the boss?”

“Will” or “would.” The usual function of “will” is to be a verbal auxiliary for expressing the simple futurity of an action, as in “Evelyn will go to Tokyo tomorrow.” As a modal, however, “will” works to convey choice, willingness, intention, consent, or habitual or customary action. Choice: “I will take the train instead of the bus.” Willingness: “I will go if you wish.” Intention: “I will prove you wrong.” Consent: “Yes, the school will admit you.” Habitual or customary action: “She will get angry over trivial things.”

In the past tense, the modal “will” inflects to “would.” To convey choice: “That year, I would fly first class rather than economy.” To convey willingness: “In my mid-twenties, I would go wherever I was assigned.” To convey habitual or customary action: “After breaking up with her fiancé, Joanna would get angry over trivial things.”

In conditional sentences, the modal “would” works to express probability or presumption of something happening in both present and past, as in “That overambitious politician (would win, would have won) hands down if not for the very serious corruption allegations against him.”

Likewise, the modal “would” conveys politeness and deference in expressing intent or desire, as in “Would you consider my daughter for that overseas job?” This differs from the rather pointed request conveyed when the modal “will” is used: “Will you consider my daughter for that overseas job?”

As quick exercise, are “will” and “would” used correctly in these two questions? “Will it rain tomorrow? If it wouldn’t, would it be a sunny day?”

Yes, both are correct. The first question uses “will” as a verbal auxiliary to express simple futurity; the second is a conditional construction where (a) the “if”-clause uses the modal “wouldn’t” to express negative possibility, and (b) where the result clause also uses the modal “would” to express expectation of a desired outcome in question form. 

“Shall” or “should.”  In American English (the English we use in the Philippines), the modals “shall” or “should” are used sparingly to state polite questions (suggestive that permission is being asked) in the first-person, as in “Should I get a taxi for you now, ma’am?” More commonly, the modal “shall” is used in formal written directives and records of corporate proceedings, as in “All workers shall be responsible for the upkeep of their respective work areas.”

This review should have given you greater confidence in using these modals. 

Read this essay and listen to its voice recording in The Manila Times:
Still baffled when to use “can” or “could” and “will” or “would”?      

Next: Are you using “were” in the indicative or subjunctive mood?       November 30, 2023   

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« Last Edit: November 26, 2023, 11:14:43 AM by Joe Carillo »