In order to make your writing clear, you need to use commas. As well as using them to separate out key information, or divide up different clauses, commas can also completely change the meaning of a ...

27 Department ofEpidemiology and Preventive Medicine, University of Regensburg, Germany 28 Faculty of Medicine and Health Sciences, Norwich Medical School, University of East Anglia Faculty of ...

Volcanoes can look like small mountains or hills. A volcano is an opening in the Earth's crust that allows magma, hot ash and gases to escape. Composite volcanoes are the most common type of volcano.