1. Ahmed is a professor of chemistry. He --------------------- very clever.

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2. The telephone range, but I didn't hear it. I -------------- been a sleep.

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3. That ----------- Ahmed. He looks very old.

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4. You ------------ learned hard to learn it.

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5. You ---------------- driven for 20 years, you drive badly.

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6. his daughter joined the faculty of medicine, she ------------------ been clever.

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