Question

Don't forget to give me a call when you
(go) to the gym​

Answer 1

when you will go to gym..

Answer 2

Don't forget to give me a call when you go to the gym​.

Explanation:

• The tense part i.e. verb is missing in the given sentence.
• The appropriate verb that can be used in the place of the blank is go only i.e. the simple present tense.
• Thus now the sentence becomes meaningful.
• The sentence means that the narrator asks the person not to forgt to give him a call when he reaches the gym.