Always go very progressively by introducing only one at a time, so you can know for sure that the following reaction (if any) is due to this food so as to avoid repeating the same mistake.
Are you ready to reintroduce because you think that you have won the battle? If so be wary. Many people fall back - from going too fast. It is best to carry on with the diet for another 60 days before you start reintroducing new food once your symptoms have all diseappeared.
You might not be healed yet and simply want to see if you are still intoterant to the food which used to provoke a reaction. Again, just go slowly, as it is true that along the healing process your intolerances will lessen.