3)作条件状语 

With time permitting, we`ll visit the Summer Palace. =  Time permitting, we`ll visit the Summer Palace. =  If time permits, we`ll visit the  Summer Palace.

4）作伴随状语 

Here are the first three volumes with  the fourth one to come out next month. =  Here are the first three volumes, the  fourth one to come out next month. =  Here are the first three volumes and the fourth one is coming out next month.

I need to be in my office by nine o’clock so I usually get up at seven o’clock. I travel to work “on the tube”. That’s 486．in London. It takes about fifty minutes. Usually, it’s 487． I can’t find anywhere to sit. I just stand. I’m always tired before I arrive at work. I don’t like the underground!

486．what people call the underground   what引导表语从句。这在伦敦称其为地铁。

487．so crowded that    so … that… 引出结果状语从句。地铁那么拥挤，我都找不到坐的地方。

488．all the crowds and the noise  句意：我妻子喜欢逛服装店，我喜欢人群和热闹。