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- strata alternation 层的交互变化
- We can follow the history of life through the strata. 我们可以通过这一层层的地层跟踪生命的历史。
- There is an alternation of black and white stripes in that cloth. 那匹布黑白条纹相间。
- They represent each society stratum. 他们代表各个社会阶层。
- The older strata gradually disintegrate. 较老的岩层渐渐风化。
- The older strata gradually disintegrated. 年代较久的地层逐渐崩解了。
- The rapid alternation of two tones either a whole or a half tone apart. 颤音两个相距一个音或半个音的音的迅速交替
- They do not constitute a separate class or stratum. 知识分子和青年学生并不是一个阶级或阶层。
- These strata, lying apparently in contact, are in fact abysmally separated. 这些表面上相触的地层实际上相隔很远。
- We are conscious of the alternation of seasons. 我们意识到季节的交替。
- To expose(rock strata)by erosion. 剥蚀因腐蚀而露出（石层）
- He hates the privileged stratum. 他憎恨特权阶层。
- The alternation are death and submission. 或死或降，任选其一。
- The meter must calibrated every alternation year. 仪表每间隔一年校准一次.
- They belong to the rich strata and never work. 他们属于富裕阶层，不干活。
- This agreement is not susceptible to alternation. 这一协议不容许更改。
- They represent all social strata . 他们代表各个社会阶层。
- To expose(rock strata) by erosion. 剥蚀因腐蚀而露出（石层）
- There are several social strata in the town. 镇上有几个社会阶层。
- This is a stratum we must win over. 这一阶层，我们是必须争取的。
