a)
Joshua works for Google.
He is a software developer.
Joshua's trainees are young graduates that have just finished university.
Joshua is Emma's trainer.
Emma is Joshua's trainee.
b)
James was employed by the government.
Ann was employed by the university.
Dan trains Sam.
Jordan was hired by a food company.
Mark James is the employee, while his employer is Dorian Clark.
You are welcome! :)