'Do Not Need To' Is Not 'Must'

Read the question as a filter, not as a topic. The question has two parts doing work: before he can borrow (a precondition for borrowing, not for entering, not for staying) and must (obligatory). Only one sentence in the notice states a precondition for borrowing: We cannot lend books to anyone who does not have a library card. The answer is he needs a library card - and the next sentence tells him how: free, at the front desk, with proof of name and address.

What misled Ken. He matched the string bring your own books and stopped reading at the word books. The full clause is You do not need to bring your own books. The negative not reverses the meaning, so the notice says the opposite of his answer. This is the commonest short-reading failure: matching a familiar word and skipping the operator in front of it.

What misled Emi. She read the Wednesday closing time and Ken's own message, and answered a question about arriving. Her statement is true (he must arrive before 5), but it is not a condition for borrowing - nothing in the notice says a late borrower is refused. She also borrowed the 5 p.m. figure from Ken's message rather than from the notice, so she is reasoning about Ken's timetable instead of the library's rule.

Transferable check. Circle the verb in the question (do / borrow / bring), then for each candidate sentence ask: is this about that verb, and is it stated as required or as not required?

Resolve the number by looking left for the countable noun it counts. The clause is we lend up to three [books] at one time. The noun books appears in the previous clause (your own books), and lend selects a thing that can be lent. So three = three books.

Why 'three days' is available as a wrong answer. At one time contains the word time, and a number sitting next to time invites the reading 'three times / three days'. The test writer knows that students attach a bare number to the nearest noun instead of to the noun that the verb requires. The unit is also deliberately left out, which is what makes the trap possible.

Two-question procedure for any bare number.

1. What verb governs it? (lend → the object must be something lendable.)
2. Which noun earlier in the sentence can that verb take? (books.)

Also check the qualifier, not just the number. up to three means 1, 2 or 3 - a maximum, not a quota. A distractor may say 'he must borrow three books', which is false; he may borrow up to three.

Generalise. In notice and poster items, numbers are almost always qualified: up to, at least, only, free, per person, at one time. Read the qualifier as part of the number. A number without its qualifier is not information.

Original negatives.

• You do not need to bring your own books.
• We cannot lend books to anyone who does not have a library card.

Positive rewrites.

1. We lend you the books, up to three at a time - bring nothing.
2. To borrow books, first get a library card. Cards are free at the front desk; bring something with your name and address on it.

Why the rewrite catches errors that re-reading does not.

• A negative sentence can be skimmed and still 'sound right' in either direction. A positive sentence has only one direction, so Ken's answer he must bring his own books becomes visibly impossible: the rewrite says bring nothing.
• Two negatives in one sentence (cannot … does not have) are the hardest pattern in the notice. Turning them into to borrow, first get a card produces one clear step.
• The rewrite also exposes the word first, which is exactly what the question's before is asking for. Ken's answer does not survive that test; the card answer does.

Classroom habit. After choosing an answer, have the student say the notice's sentence aloud in their own positive words. If the sentence cannot be said positively without contradicting the chosen answer, the answer is wrong.