Error Spotting – Choose the part (A–D) that contains the grammatical error, or choose No error if the sentence is fully correct. Sentence (parts correspond to options below): A) Since it was a memory test B) the students were instructed C) to learn the D) passage by heart.

Introduction / Context:
This item tests mastery of fixed idioms. The correct idiom in English for memorizing exactly is learn by heart, not learn with heart.

Given Data / Assumptions:

• Instructional frame: the students were instructed to learn …
• Target idiom: by heart
• Incorrect preposition in the original: with heart

Concept / Approach:
Idioms are conventionalized; their prepositions are not freely interchangeable. By heart uniquely signals memorization; with heart suggests emotion or enthusiasm, which changes meaning.

Step-by-Step Solution:

Verification / Alternative check:
Comparable idioms: know by heart, recite by heart. None allow with.

Why Other Options Are Wrong:

• A) Since as a causal subordinator is grammatical.
• B) Passive instruction frame is standard.
• C) Infinitival to learn the is fine.

Common Pitfalls:
Translating idioms literally from other languages often leads to wrong prepositions. Memorize the fixed form by heart.

Final Answer:
Option D contains the error. Use passage by heart.