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.
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Question: Butter cakes are traditionally made using a creaming method , in which the butter and sugar are first beaten until fluffy to incorporate air into the butter .

Answer: Butter cakes are often made by beating the butter and sugar until fluffy .

Question: Katerini ( , " Kateri ni " , -RSB- ) is a city and municipality in northern Greece , the capital city of province of Pieria ( regional unit ) in Central Macedonia , Greece .

Answer: Katerini is a Greek city which is the capital of Pieria prefecture in the region of Macedonia .

Question: The thoracic diaphragm , or simply the diaphragm , is a sheet of internal skeletal muscle in humans and other mammals that extends across the bottom of the thoracic cavity .

Answer:
The diaphragm is a muscle that is at the bottom of the ribcage of mammals .