WILL GIVE BRAINIEST FOR FIRST ONE THAT ANSWERS BUT HAS TO BE RIGHT
Highlight signal words in the passage.

Napoleon entered the Egyptian capital, Cairo, on July 21. There he took over an elegant palace to serve as the headquarters for his scholars and scientists. They began work immediately and acquired the nickname "the donkeys" because of the donkeys they rode on their expeditions into the countryside.

—The Riddle of the Rosetta Stone,
James Cross Giblin

Which signal word is used in the passage?

serve
because
began
into

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