By computer simulations and experimental tests, this control structure can reduce one and two tonal frequency noises. 通过仿真和测试表明，该控制结构能有效消除噪声中所含的单周期噪声和双周期噪声。
You can no longer spread the different controlling parts of a control structure across file boundaries. 不能将一个完整的控制结构分散在不同的文件中。
