HEC HAT common mistakes
HEC HAT · Understand the traps and how to avoid them.
On vocabulary items, chooses a near-synonym that fits only one sense of the word, without checking part of speech or the sentence's register, and marks the first plausible gloss.
Word lists are learned as one-word equivalents, so the candidate treats synonyms as interchangeable and does not test the word in context.
What to do instead
Predict a word or phrase from the sentence before reading options, note the required part of speech, substitute each option back into the original sentence, and keep a synonym-cluster notebook with collocations and connotation labels.
In grammar and sentence-correction items, repairs only the underlined phrase and ignores parallelism, agreement with a distant subject, or the logic of the whole sentence.
Reading left to right encourages local repair; the candidate fixes the visible error without checking how the phrase functions in the sentence skeleton.
What to do instead
Identify subject-verb-object and list parallel items before reading options; test each option against the full sentence, not just the underlined span; remove long modifiers to expose agreement and parallelism.
In reading comprehension, selects an option because it repeats a passage keyword or matches personal knowledge, even when the passage does not state or imply it.
Keyword matching feels efficient under time pressure, and prior knowledge fills gaps that the passage leaves open.
What to do instead
For every option, cite the line or paragraph that supports it; reject choices supported only by a keyword match; label each choice as stated, inferable in one step, or outside the passage.
In data interpretation, computes percentage change as new divided by old, adds percentage points to a base as if they were percent, or ignores units on axes and table headings.
Formula confusion and rapid skimming cause the candidate to grab familiar numbers without anchoring them to units or a base value.
What to do instead
Write the formula before calculating: percent change equals (new minus old) divided by old times 100; label every number with its unit; convert all quantities to a common unit; estimate the answer first to catch scale errors.
Sets up rate, work, and average problems with the wrong base, such as averaging speeds with (v1 plus v2) divided by 2 for equal distances, or adding times instead of rates.
Pattern-matching to a familiar formula replaces defining variables and checking what is actually being averaged or combined.
What to do instead
Define each variable with units in one line; use total distance divided by total time for average speed; add rates for combined work; substitute simple numbers to sanity-check the setup before solving.
In geometry items, assumes lines are parallel or perpendicular, or angles are equal, because the drawing looks that way, and uses unstated properties in the proof.
Diagrams are trusted as evidence, especially when the figure appears to scale and the answer choices are close.
What to do instead
Mark only given information on the figure; redraw an extreme sketch; use only stated properties and theorems; check angle sum, triangle inequality, and whether a length or angle is actually determined.
In ordering and grouping puzzles, keeps constraints in memory and answers a 'must be true' question by checking one arrangement that happens to work.
Without an external diagram, the candidate confuses a possible arrangement with a necessary consequence and stops at the first satisfying case.
What to do instead
Draw slots or a grid and write each constraint as a symbol; for 'must' questions try to construct a counterexample; for 'could' questions find one valid arrangement; eliminate options that violate any single constraint.
Confuses necessary and sufficient conditions, treating 'A only if B' as 'if B then A', or accepts an assumption as if it were the argument's conclusion.
Everyday conditional language is directional and ambiguous, so the candidate reverses the arrow or misses what the argument depends on.
What to do instead
Translate every conditional into if-then form and write its contrapositive; for assumption questions, negate the candidate choice and check whether the argument collapses; label conclusion and premises explicitly.
In strengthen and weaken items, picks a choice that is on the same topic as the passage but does not affect the gap between evidence and conclusion.
Topic-word matching feels relevant, so the candidate stops at the first familiar-sounding option instead of testing logical impact.
What to do instead
Write the conclusion and premises in one line, state the gap as a question, then ask whether each choice makes the conclusion more or less likely; discard choices that merely restate evidence or introduce unrelated scope.
In subject-knowledge items, applies a memorized formula or definition without checking its assumptions, population, or boundary conditions, and ignores qualifiers such as EXCEPT, initial, or most likely.
Revision is organized around rote recall, while the exam presents applied scenarios whose correct answer depends on when a rule does and does not hold.
What to do instead
Underline qualifiers before evaluating options; for each formula list its assumptions and failure cases; practise scenario-based and negative items; justify why each distractor fails, not only why the chosen option is familiar.