In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.

Q: In humans , the pigmentation of the iris varies from light brown to black , depending on the concentration of melanin in the iris pigment epithelium ( located on the back of the iris ) , the melanin content within the iris stroma ( located at the front of the iris ) , and the cellular density of the stroma .

A: In humans , the pigment of the iris varies from light brown to black .
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Q: The United World College of South East Asia ( UWCSEA ) is an independent international school in Singapore , and a member of the United World College ( UWC ) movement .

A: United World College of South East Asia ( UWCSEA ) is an independent school in Singapore .
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Q: The European Capital of Culture is a city designated by the European Union ( EU ) for a period of one calendar year during which it organises a series of cultural events with a strong pan-European dimension .

A:
The European Capital of Culture is a city chosen by the European Union for a period of one calendar year .
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