English grammar error-spotting (parallelism of infinitives and correct verb form): Read the sentence in four parts (A–D) and identify the erroneous part; select ‘‘No error’’ only if the sentence is fully correct: ‘‘The method suggested in the lecture / enables a student to learn more quickly / and to have remembered for a longer period of time. / No error.’’

Given data

• A: ‘‘The method suggested in the lecture’’
• B: ‘‘enables a student to learn more quickly’’
• C: ‘‘and to have remembered for a longer period of time.’’
• D: ‘‘No error.’’

Concept / ApproachMaintain parallel structure: ‘‘to learn’’ should pair with ‘‘to remember’’ (not ‘‘to have remembered’’). The perfect infinitive changes meaning and breaks symmetry.

Step-by-step evaluationCorrect parallelism → ‘‘… enables a student to learn … and to remember …’’Hence, Part C is the error: ‘‘and to have remembered for a longer period of time.’’

Correction‘‘… enables a student to learn more quickly and to remember for a longer period of time.’’ (Optionally add an object: ‘‘to remember it …’’)

Common pitfalls

• Mixing infinitive forms within coordinated structures.

Final Answerand to have remembered for a longer period of time.