Everyone knows what is anchor text.
In the following text, terms like
publishing,
graphic design,
placeholder text and
graphic are anchor text, which are hyper linked to certain URL.
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"In publishing and graphic design, lorem ipsum[1] is placeholder text (filler text) commonly used to demonstrate the graphic elements of a document or visual presentation..."
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Now read the following sentence...
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"Get more information about latest iPhone, iPhone cases, iPhone battery and iPhone insurance."
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You know that these links are not natural. It will be considered total spam by search engines.
Try to be natural with anchor text and don't be aggressive with them.