Concurso Nacional Unificado (CNU) common mistakes
Concurso Nacional Unificado (CNU) · Understand the traps and how to avoid them.
Answering interpretation questions about a literary excerpt by matching a keyword from the text to an option, without locating the line that supports the answer.
Candidates trained on short factual questions treat literature items as recall of authors and schools; under time pressure they pick the option that repeats a familiar word (e.g., 'romantismo', 'ironia') instead of testing the interpretation against the passage.
What to do instead
For every interpretation item, underline the exact excerpt (or two excerpts) that justify the chosen option and write one sentence connecting excerpt to option. If no excerpt supports it, discard the option. Practise on 10 short poems/crônicas per week, timing 2 minutes per item.
Confusing textual cohesion with textual coherence, or classifying a cohesive device (e.g., 'portanto', 'esse') as a grammatical error rather than as a linking or referential mechanism.
Grammar-school habits lead candidates to judge sentences by prescriptive rules rather than by function in the text; they memorise lists of connectives without linking each to the logical relation (opposition, conclusion, explanation) it signals.
What to do instead
Build a two-column table: connective → logical relation, and pronoun/ellipsis → what it refers to. Then answer 20 items where you must state the relation and the referent before choosing. Review the difference between cohesion (surface links) and coherence (global meaning) with one worked example each.
Reading English questions as translation tasks, translating word by word and choosing the option that sounds most natural in Portuguese rather than the one that matches the English text.
Candidates with intermediate English rely on cognates and literal transfer; false friends ('actually', 'eventually', 'library') and syntactic differences (adjective order, gerund after prepositions) produce plausible but wrong answers.
What to do instead
Practise skimming for the main idea first, then scanning for the specific line. Keep a personal false-friend list and test yourself weekly. For grammar items, identify the grammatical category being tested (tense, preposition, connector) before reading the options.
Solving logical reasoning items by intuition instead of formalising the statements into symbols or a truth table, then checking only one or two cases.
Items look familiar and candidates rush; conditional statements ('se... então') are treated as biconditionals, and 'somente se', 'necessário' and 'suficiente' are read interchangeably.
What to do instead
Always write the argument in symbols (P → Q, ¬Q ∴ ¬P) and test validity with a truth table or by trying to construct a counterexample. Drill the equivalences: P → Q ≡ ¬Q → ¬P ≡ ¬P ∨ Q, and distinguish necessary from sufficient conditions with 15 targeted items.
Reading a percentage-increase or proportion problem and applying the rate directly to the wrong base (e.g., calculating a discount on the final price, or adding percentages instead of compounding).
Word problems hide the base; candidates latch onto the first number mentioned and skip the step of identifying the reference value. Successive percentage changes are treated as additive.
What to do instead
Before calculating, write 'base = ___' and 'what is asked = ___'. For successive changes use factors (1.2 × 0.9), never sums. Redo every wrong item by writing the full equation, then solve three variants with changed numbers to confirm the method transfers.
Answering legal-concepts items from television or everyday usage, for example treating 'princípio da legalidade' as 'whatever the administrator finds reasonable' or mixing up legality and discretion.
Noções de Direito is studied by reading summaries without the constitutional text; abstract principles are memorised as slogans, so items that apply a principle to a concrete case defeat the candidate.
What to do instead
Anchor each principle in its constitutional article (e.g., art. 5º, II; art. 37, caput) and write one concrete example of a violation. For each topic, produce a three-line card: rule, constitutional basis, example. Test yourself by classifying hypothetical administrative acts.
Mixing up the roles of the three branches and the federative entities, attributing to the Union competences that belong to states or municipalities, or confusing exclusive, common and concurrent competences.
The lists in arts. 21–24 of the Constitution look similar; candidates memorise 'who does what' by sound rather than by the criterion (exclusive = one entity; common = all cooperating; concurrent = Union sets general rules).
What to do instead
Make a three-row table (exclusive, common, concurrent) with the criterion in the header and 5 examples per row, citing the article. Answer application items by naming the article before the option. Review monthly with spaced repetition.
Treating 'Realidade Brasileira e Atualidades' as general knowledge and answering from impressions about current events, without dates, institutions or data.
News is consumed passively through headlines and social media; candidates cannot distinguish a proposal from an enacted law, or a federal programme from a state one, and they rely on outdated information.
What to do instead
Keep a weekly one-page log: event, date, institution responsible, stage (proposal/approved/in force), source. Verify each entry in a primary source (official gazette, agency site). Before the exam, revise the log and practise explaining each event in two sentences with its date.
Studying the specific block (Conhecimentos Específicos) only through isolated facts, without connecting them to the thematic axis of the block or to the other blocks.
The specific block carries the most weight, so candidates buy large fact summaries and memorise definitions, but CNU items are often situational and interdisciplinarity is expected; isolated facts do not survive an applied question.
What to do instead
For each specific topic, write a 5-line summary: definition, legal/policy basis, practical example, common error, link to another block (e.g., law or current affairs). Solve at least 20 applied items per topic and rewrite each wrong answer as a corrected paragraph.
Managing time and format poorly: spending too long on Portuguese and literature items, leaving no time for the specific block, and misreading the answer sheet or the item command ('incorrect', 'except').
The exam is long and the blocks are weighted unequally; without a rehearsal, anxiety pushes candidates to perfect the first questions, and the negative command is missed because of speed.
What to do instead
Run full timed mock exams with a fixed per-block budget (e.g., 2 minutes per item, hard stop), marking uncertain items to return to. Circle the command word ('correta', 'incorreta', 'exceto') before reading options. Simulate the answer sheet transfer in the last 15 minutes.