Examples
yīn wèi因为shì是xīng qī tiān星期天，chāo shì超市fēi cháng非常yōng jǐ拥挤。
因为是星期天，超市非常拥挤。
It being Sunday, the supermarket was very crowded.
上下班时间，公共汽车特别拥挤。
The busses are especially crowded during rush hour.
销售区相对来说不算拥挤。
The sales floor was relatively uncrowded.