What does one do if they catch up with the imam in the second rak'ah of a four-rak'ah prayer?

Question:
May Allah reward you. This sister says: If I enter a four-rak'ah prayer and the imam is in the second rak'ah, what do I do?

Answer:
You enter with him and consider the rak'ah you caught up with as your first rak'ah. You sit with the imam for the first tashahhud. Then, when he stands up, you stand up with him and consider this rak'ah as your second rak'ah. Then you stand up with him for the third rak'ah, which is the fourth for the imam and the third for you. When the imam says the taslim, you stand up and perform one rak'ah, sit for the tashahhud, and then say the taslim. The sitting for the first tashahhud is dropped for you; the first tashahhud and its sitting are dropped. Yes.