题目内容
（ ）指的是：当在电介质的极化方向施加电场，这些电介质就在一定方向上产生机械变形或机械压力，当外加电场撤去时，这些变形或应力也随之消失的现象。
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压电材料主要包括：
正压电效应指的是：某些电介质，当沿着一定方向对其施力而使它变形时，内部就产生极化现象，同时在它的一定表面上产生电荷，当外力去掉后，又重新恢复不带电状态的现象。
Translate theunderlined wordsinto Chinese.1. Other than a degree, from a college education I plan to pursue higher learning, to begin a career, and to make history in my family. (Text B, Unit 1)2. The job requires a high degree of skill.3. It will probably be a few degrees colder by the weekend.4. … a device in their eyeglasses may suggest a few meal options and then automatically place an order for them. (Text A, Unit 2)5. True leaders do not just give orders, but take time to listen to the advice of those around them.6. The doctor ordered me to stay in bed.
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