Lin Yao's cheating method was very covert: he bribed a staff member at the test center to package a specially processed listening tape before the test. The tape had very slight beeps on some key questions, which ordinary people could not hear, but the special headphones he wore could pick up the sound.
For the multiple-choice part, he used two special inks to paint the answer sheets. One will disappear automatically within three hours after the exam, and the other is normal. He first applied disappearing ink to ensure that he answered correctly. After the exam, the traces disappeared and the invigilator could not detect any abnormalities even if he checked the answer sheet.
Lin Hui was more simple and rude: he bribed a student with good grades in the back row and agreed on a hand signal. The multiple-choice questions rely on peeking. For the subjective questions, the student will deliberately move the answer sheet to the side.
