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- envelope approximation circuit 包络近似电路
- slowly-varying envelope approximation 缓变包络近似
- Have you stuck down the back of the envelope? 信封背面开口处贴牢了吗？
- He steamed the stamp off the envelope. 他用蒸汽把信封上的邮票揭下来。
- He glued a stamp onto the envelope. 他把邮票贴在信封上。
- As he picked up the envelope, a key dropped out. 他拣起信封时，一把钥匙掉了出来。
- As she picked up the envelope, a key dropped out. 她拾起信封时，一把钥匙掉了出来。
- Put a stamp on the envelope, will you? 在信封上贴张邮票，好吗？
- He stuck a stamp on the envelope. 他在信封上贴上邮票。
- There are two breakers in this circuit. 这个电路里面使用了两个断路器。
- She opened the envelope with her fingertips. 她用指尖弄开了信封。
- A replaceable printed circuit board. 一种可替换的印制电路板。
- The envelope's seal was torn open. 信封封缄被撕开了。
- The (flap of the) envelope was unstuck. 信封(的封口)没粘住。
- Binvalidation of the Slowly-Varying Envelope Approximation and Producing and Eliminating of the Spatial Singularity for Ultrashort Pulsed-Beam Propagation in Free Space 超短脉冲光束传输缓变包络近似理论的失效和空间奇异性的形成与消除
- The circuit of the city walls is three miles. 环绕本市城墙的周长是三英里。
- There are several enclosures in the envelope. 信封内装有几份附件。
- An envelope or wrapper for mail. 封套，信封为邮寄而制的信封或封套
- There must be a break in the circuit. 电路中一定有断路。
- A short circuit will blow the fuse. 短路会烧断保险丝的。
