Question

I may go to the (1) / swimming class tomorrow (2) / if I have recovered (3) / from the cold.
(4) / No error (5)

Answer 1

The wrong part is option 3.

If I have recovered from cold is not grammatically correct.

The correct sentence would be -

I may go to the swimming class tomorrow if I recover from the cold.

Explanation -

The entire sentence is present tense.

So I have recovered is present perfect and does not fit in the sentence grammatically.