3 sentences for 往来 (wǎng​lái — back and forth)

1. 大街上车辆往来不断。

   dà​jiē shàng chē​liàng wǎng​lái bù​duàn.

   Traffic flows incessantly on the street.

   Source: Dong Chinese Dictionary

2. 苏沪两地之间的交通往来现在变得非常便捷。

   sū Hù liǎng dì zhī​jiān de jiāo​tōng wǎng​lái xiàn​zài biàn de fēi​cháng biàn​jié.

   Travel between Suzhou and Shanghai has become very convenient now.

   Source: Dong Chinese Dictionary

3. 丝绸之路上商贾往来不断，极大促进了东西方的贸易交流。

   Sī​chóu​zhī Lù shàng shāng​gǔ wǎng​lái bù​duàn, jí dà cù​jìn le dōng​xī​fāng de mào​yì jiāo​liú.

   The constant stream of merchants along the Silk Road greatly promoted trade and exchange between the East and the West.

   Source: Dong Chinese Dictionary