Must vs. should: the one-word trap in CFA Level I Ethics
Talk to candidates after an Ethics-heavy mock and you hear the same story: "I knew the Standard. I still picked the wrong answer." Very often the question wasn't testing the Standard at all. It was testing one modal verb.
The CFA Institute Code and Standards draw a hard line between two kinds of guidance. Requirements — written with must, shall, or stated as obligations — are things a member has to do; failing to do them is a violation. Recommendations — written with should, may, encouraged — are best practice; skipping them is not a violation.
The exam loves to sit a question exactly on that line.
The classic: seven-year record retention
Standard V(C) Record Retention is the textbook example. The Standards recommend keeping records for at least seven years when no regulatory rule says otherwise. Candidates memorize "7 years" as a fact — then the exam asks:
"According to the Standards, members must retain investment records for a minimum of seven years." True or false?
If you stored "7 years" without the modal verb, you answer "true" — and lose the point, because seven years is a recommendation. The number was never the test. The verb was.
The same pattern shows up elsewhere. Encouraging your employer to adopt a code of ethics or compliance procedures? Recommended, not required. Disclosing referral fees to clients and employers? Required under Standard VI(C). Two facts that sound similar in a summary sheet — on opposite sides of the must/should line.
Why non-native English speakers get hit harder
Here's the part most prep material never mentions: in many languages, the everyday translation of must and should collapses into a single word, or into two words nobody keeps strictly apart. When you study in English but think in your native language, the modal often falls away in your notes — you remember the action ("keep records 7 years") without its legal weight.
That's not a knowledge deficit. It's a translation loss. And it's fixable with reading discipline, not more study hours.
A three-step habit that stops the bleeding
- Underline the modal before reading the choices. In every Ethics question, physically mark must / should / may / required / recommended in the stem. Decide "requirement or best practice?" before you look at a single answer option.
- Store facts WITH their verb. In your notes, never write "7-year retention." Write "should retain 7 years (recommendation)." The verb is part of the fact.
- Read rationales even when you're right. The reasoning style — required vs. recommended, violation vs. no violation — is the actual skill being tested. Answer explanations teach it faster than re-reading the curriculum.
Quick reference
| Language in the Standards | Meaning | If skipped… |
|---|---|---|
| must, shall, "is required to" | Requirement | Violation |
| should, may, "is encouraged to" | Recommendation (best practice) | Not a violation |
While you're at it, watch the modal's two siblings in question stems: least likely (candidates skimming under time pressure drop the negation) and most appropriate (two choices can be defensible — the exam wants the best one, not the only true one). All three are reading traps, not knowledge traps.
Want the full list? We put the Ethics wording traps plus the FSA traps into a free bilingual (Vietnamese/English) PDF — no email, no signup: download the Ethics + FSA rescue sheet.
And if English isn't your first language: Charter5m teaches every Level I concept in English with your native language one tap away — so exam wording stops being the thing that costs you points.
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