Rewrite the following sentences, keep the meaning unchanged

Rewrite the following sentences, keep the meaning unchanged.
 I was standing right next to her. She didn’t recognize me. (but)

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 You work too fast or you make so many mistakes. (If)

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They couldn’t drive fast. The road was slippery. (so)

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Lan didn’t go to the zoo yesterday. Nga didn’t go to the zoo yesterday. (either)

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 My friends enjoy singing. We enjoy singing. (too)

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