Review and practice: During each review session, actively use the target material in speaking, writing, or listening exercises.

复习和练习：在每次复习期间，在口语、写作或听力练习中积极使用目标材料。

Applying Spaced Repetition in English Learning: Identify the target material: Choose the vocabulary words, grammar rules, or idiomatic expressions you want to learn.

在英语学习中应用间隔重复： 识别目标材料：选择你想学习的词汇、语法规则或惯用语。

PCR, or polymerase chain reaction testing, targets the virus's genetic material in the body and is used to diagnose someone who is currently infected.

PCR 或聚合酶链反应检测以体内病毒的遗传物质为目标，用于诊断当前感染的人。