BD Police ASI Written common mistakes
BD Police ASI Written · Understand the traps and how to avoid them.
In Bangla grammar items, guessing the correct sadhu-to-cholit or cholit-to-sadhu conversion by ear instead of applying the sound-change rules, so verbs like 'করিল' or 'হইল' are mapped wrongly.
Candidates read literature fluently but never drilled the systematic correspondence between the two registers, so they rely on spoken intuition that does not cover archaic forms.
What to do instead
Build a two-column table of the 40-50 most frequent sadhu/cholit verb and pronoun pairs, memorise the pattern rules (e.g. '-ইল' to '-ল/লো', 'হইল' to 'হল'), then convert 20 short sadhu passages to cholit weekly and check each against the table.
On Bangla literature questions, confusing the era and authorship of major figures, for example attributing 'Meghnad Badh Kavya' to Rabindranath or placing Michael Madhusudan in the post-Tagore period.
Authors are studied as isolated names rather than as a timeline, so period markers (pre-1857, Bengal Renaissance, Kallol era) never get anchored to specific works.
What to do instead
Draw a single horizontal timeline from the Charjapad to the 1950s and place each major author, work and literary movement on it; redraw it from memory each week until author, century and genre are recalled together.
In English error-detection and fill-in-the-blank items, choosing the option that sounds natural in speech, such as 'He don't' patterns, subject-verb mismatches, or wrong prepositions like 'discuss about'.
Everyday spoken English habits and Bangla sentence structure interfere with formal written grammar, and candidates rarely test each option against a rule.
What to do instead
For every grammar item, explicitly name the rule being tested (subject-verb agreement, article use, preposition collocation, tense sequence) before selecting; keep a personal error log of the 30 rules you miss and review it before each mock.
In English literature items, matching a quotation to the wrong author or confusing characters across texts, for example mixing Shakespeare's tragedies or attributing Romantic poems to the wrong poet.
Quotations are memorised without their source context, and candidates prepare from summaries rather than from author-work-quote triplets.
What to do instead
Maintain a three-column register (author, work, one identifying line or character) for the syllabus authors and self-test by covering one column; add only verified entries and drop any quote you cannot confirm.
In arithmetic word problems, computing an intermediate value and submitting it as the answer, such as giving the discount amount when the question asks for the final price, or giving speed when it asks for time.
Under time pressure candidates stop reading at the first number they can calculate, and multi-step problems are attempted without a written plan.
What to do instead
Underline the actual question word (how much, how many, what percentage) before starting, write the required unit beside it, and do a final 5-second check that the computed quantity and unit match what was underlined.
In percentage, ratio and average problems, setting up the equation with the wrong base, for example applying a 20% increase then a 20% decrease and answering 'no change', or taking the original price as the base after a markup.
The concept of the base quantity is not fixed in memory, and candidates pattern-match to familiar question types instead of identifying what the percentage is taken of.
What to do instead
Before solving, write 'base = ___' explicitly and test with concrete numbers (start with 100) to verify the result; practise 10 successive-percentage problems until the non-reversibility of percentage change becomes automatic.
On Bangladesh affairs questions, mixing up dates, order and authorship of major events, such as the dates of the Language Movement, the Six Point Movement, the 1970 election and the Mujibnagar government formation.
Facts are memorised as a flat list of years without a causal sequence, so adjacent dates overwrite each other in recall.
What to do instead
Build a dated timeline of 1947-1971 with cause and effect links between entries, and rehearse it by reciting the sequence aloud in order; quiz yourself on 'what happened immediately before and after' each event rather than on isolated years.
On international affairs and organisational questions, guessing headquarters cities, founding years and current officeholders, or relying on outdated information about membership and leadership.
General knowledge is absorbed passively from social media and old guidebooks, with no verification step and no date attached to the fact.
What to do instead
Keep a fact sheet with a 'verified on' date beside each entry, source it from official organisational sites, and refresh the volatile items (heads of state, secretary-generals, memberships) monthly; discard any entry you cannot re-verify.
On computer fundamentals items, confusing storage units and their order, mixing up RAM and ROM roles, or misidentifying which component performs a given function such as processing versus temporary storage.
Terms are learned as vocabulary lists without a mental model of how a computer actually processes and stores data.
What to do instead
Sketch the machine as a flow diagram (input, CPU with ALU and control unit, primary memory, secondary storage, output) and place each term on the diagram; memorise the unit ladder (bit to byte to KB to MB to GB to TB) with the factor of 1024 and self-test both directions.
On physics and general science items, applying a formula by symbol-matching without checking units or physical conditions, for example using the speed-of-light value in the wrong unit or treating a vector quantity as a scalar.
Formulas are memorised as strings of letters rather than as relationships with defined units and valid conditions, and SI prefixes are not converted consistently.
What to do instead
For every numerical science item, write the given quantities with units, convert all to SI first, state the formula, then substitute; keep a one-page sheet of quantities with their SI units and whether they are scalar or vector, and review it before each practice set.
On chemistry items, predicting products or bonding behaviour from the name of a substance rather than from its formula and reaction type, so acids, bases and salts are mismatched in neutralisation and displacement questions.
The periodic table and common reaction patterns are not internalised, so candidates rely on rote associations that break down on unfamiliar examples.
What to do instead
Drill the first 20 elements with symbols and valencies, then practise writing and balancing 15 common reaction types (neutralisation, displacement, combustion, decomposition) until you can predict the product class from the reactants alone.
On geography items, locating rivers, districts or countries by vague memory instead of a mental map, leading to errors about which river a tributary joins or which district borders which.
Physical and political geography are studied as text lists without spatial practice, so relative positions are never encoded.
What to do instead
Practise with a blank outline map of Bangladesh and one of the world weekly, labelling rivers, divisions and neighbouring countries from memory, then checking and correcting; describe each feature by its neighbours and flow direction, not just its name.
On environment and disaster management items, giving generic answers such as 'plant trees' or 'raise awareness' where the question asks for a named mechanism, agency or cyclone-category detail.
Candidates treat this domain as opinion-based rather than factual, and do not learn the institutional framework (cyclone warning signals, disaster management cycle phases, responsible bodies).
What to do instead
Learn the disaster management cycle as four named phases with an example action in each, memorise the cyclone warning signal numbers and their meanings, and list the roles of the relevant national agencies; answer with the specific term, not a slogan.