Answer: What my father has to do is wear a uniform and check everyone's identity.
Explanation:
A cleft sentence is a complex sentence that can also be expressed by a simple sentence without changing its meaning. Cleft sentences usually highlight the information that is new to the listener
In this example, we need to form a Wh-cleft sentence, which is introduced by the word "what," and usually starts with the information that has already been understood, and adds the new information in the following clause.
