It can serve as a substitute.
When something serves as something, it acts as a replacement. You can always use the verb 'to be' in place of 'to serve as'. Here are some samples:
- An uncle serves as the boy's guardian while his parents are away.
- The school will serve as the location for the disaster relief center.
It is commonly grown all over the world.
When something is common, it is easy to notice or find. Commonly is the adverb. Here are a few sample sentences.
- That language is commonly spoken here.
- That fact is not commonly known by most people.
It is the filling part of a lot of dishes.
When something is filling, it makes one full or not hungry. The filling part is the main part of a meal or dish that makes the eater full. It fills the persons stomach. Notice the following:
- The meal was very filling.
- The potato salad was very filling.
Rice is a staple grain.
A staple is the main part of a diet, or the main thing people eat. Some staple foods in various countries are corn, potatoes, and rice. Notice the following:
- Wheat is the staple ingredient for bread.
- Corn is the staple of that diet.
Soups are widely available.
When something is widely available, that mean you can find it anywhere or in most places. The item has a wide range. If something is widely available, it is easy to find or get. Notice the following:
- Phone booths are not as widely available as before due to cell phones.
- Coffee is widely available in most cities.