Step 1: Decoding 'Unless' in Conditionals:
The word “unless” is mathematically equivalent to “if not.” Therefore, to replace “unless” with an “if” clause, we must introduce a negative element into that clause to maintain the same meaning.
Step 2: Adjusting Verb Tenses and Auxiliaries:
The sub-clause is in the simple present tense (“he gets”). To negate this in the active voice, we use the auxiliary verb “does not” combined with the base verb form: “if he does not get...”
Step 3: Constructing the Final Conditional Sentence:
Combining this with the main clause gives us: “If he does not get a uniform, he won't join the team.”