Shiek my question is if you come for taraweeh prayer and they already finished praying Ishaa and they are on the first rakat of the two rakats and You joined them when they finished should add two more rakat to complete your ishaa or you should do a whole ishaa(4 rakat) ?

After the imam concludes his prayer, you should stand up and pray 2 rakahs to finish your Isha.*

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