PTELook at the text below. In 35 seconds, you must read this text aloud as naturally and clearly as possible. You have 35 seconds to read aloud.

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The hardness of materials is determined by the strength of the chemical bonds that are formed between the electrons of the neighboring atoms. For example, the bonds in diamond are very strong, so it is one of the hardest materials known. The bonding is rooted in the laws of quantum mechanics.

PTERead Aloud: #1340

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