1. When our delegation arrived at the university, the conference had already begun.
2. He told me he had already paid.
3. It is the second time she has made that mistake.
4. Nora looked wonderful after she had lost a few kilos.
5. Fred had phoned me before I left home.
5. When the police arrived, the car had gone.
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1. Past Simple; Past Perfect.
2. Past SImple; Past Perfect.
3. Present Simple; Present Perfect.
4. Past Simple; Past Perfect.
5. Past Perfect; Past Simple.
6. Past Simple; Past Perfect.