来回移动

The objective conditions make people happy and sad. The happy and sad mood swing like a pendulum.

人因客观条件的牵引而兴之乐与哀，永远就是这样如钟摆般来回地交换移动。

I especially enjoyed the way he drew elipses on the court as he danced to-and-fro, preparing for his next shot.

我特别享受他在场上来回的椭圆形移动，随时准备好他的下一击。

The pool, that just days before I had been planning to clean and make ready for some early spring swimming, was a block of blue-green ice, and it seemed to fascinate them.

来回的路上见不到一辆移动的汽车，盖满白雪的汽车比温顺的绵羊还老实而安静地停在傍山的路旁。

We will see more and more activist government policies that distinguish economic activities according to the nationality of the actors.

我们将看到越来越多激进的政府政策，这些政策根据企业的国籍来区分经济活动。

If we can prove the independence of an axiomatic system, then we can guarantee the conciseness of this system, ie.

如果能够证明某个一阶谓词系统的独立性，那么就能够保证该系统的建立是精炼的，即没有任何一条公理或推理规则是多余的。