Idiomatic Expressions with Modal Verbs — may well / may as well

Idiomatic expressions using modal verbs are common targets on examinations. Learn to distinguish their meanings accurately.

Basic Rules

Frequently used idiomatic expressions with modal verbs:
① may well + base-form verb: “may naturally do something / will probably do something”
“You may well say so.（It is natural for you to say so）” “She may well be sleeping now.（She is probably sleeping now）”
② may as well + base-form verb: “may as well do something / might as well do something” (a reluctant choice)
“We may as well start now.（We may as well start now）”
③ might as well + base-form verb (as base-form verb): “might as well do something (doing one thing is no different from doing another)”
“You might as well throw your money away as lend it to him.（Lending him money is the same as throwing it away）”
④ cannot help + gerund / cannot help but + base form: “cannot stop oneself from doing something”
“I cannot help laughing.” “I cannot help but laugh.”
⑤ cannot ... too ...: “no matter how much one does something, it is never too much”
“You cannot be too careful in choosing your words.”
⑥ do nothing but + base-form verb: “do nothing but do something”
“He does nothing but complain.”
⑦ would rather A than B: “would prefer A to B”
“I would rather walk than take a taxi.”

Points to Remember

① Difference between may well and may as well (frequently tested in university entrance examinations):
- may well: “it is natural that ~ / ~ will probably happen” (a conjecture with a reason)
- may as well: “may as well do ~” (a reluctant choice)
A way to remember: with only “well,” “naturally” leads to “it is reasonable.” “As well” means “to the same degree,” leading to “it is acceptable to do it as another option.”
② cannot help -ing / cannot but + base form / cannot help but + base form: all three patterns mean “cannot help doing something.”
- I cannot help crying.
- I cannot but cry. (old-fashioned)
- I cannot help but cry. (conversational)
③ would rather + subject + past tense: “would prefer that the subject do something” (a desire) “I would rather you didn't smoke here.（I would prefer that you not smoke here）” ← subjunctive-like; note the past tense.
④ may + optative: “May you be happy!（I hope you will be happy）” ← a formal prayer. It is old-fashioned but appears in literature and speeches.

Practice

1. Translate “It is natural that she was surprised” into English using may well.
2. Translate “Since it is raining, we may as well stay home” into English using may as well.
3. Translate “You cannot be too careful about your health” using cannot be too careful.