Помощь с английским языком

Ричард Гордон, здравствуйте. В этом задании в некоторых временах нужно менять индикаторы времени.
After graduating from a university lawyers take one more exam.
After graduating from a university lawyers took one more exam.
After graduating from a university lawyers will take one more exam.
After graduating from a university lawyers are taking one more exam.
After graduating from a university lawyers were taking one more exam.

After graduating from a university lawyers will be taking one more exam.
Аfter graduating from a university lawyers have taken one more exam.(ОШИБКА. Нужно менять часть с 'after'!).
Аfter graduating from a university lawyers had taken one more exam. (ОШИБКА. Нужно менять часть с 'after'!)
After graduating from a university lawyers will have taken one more exam (так сказать нельзя, начало придётся менять на 'by the moment of graduating/'by graduating'.
After graduating from a university lawyers had been taking one more exam. ОШИБКА. Нужно всё менять!
After graduating from a university lawyers will have been taking one more exam... то же самое. Так не говорят, нужны дополнительные слова, типа: 'After graduating from a university lawyers will have been taking one more exam for two days before they get their certificates)'. По-другому выбор времени Future Perfect Continuous не правомерен.

After graduating from a University lawyers take one more exam.
After graduating from a University lawyers took one more exam.
After graduating from a University lawyers will take one more exam.

After graduating from a University lawyers are taking one more exam.

After graduating from a University lawyers were taking one more exam.
After graduating from a University lawyers will be taking one more exam.

After graduating from a University lawyers have taken one more exam
.After graduating from a University lawyers had taken one more exam.
After graduating from a University lawyers will have taken one more exam.
.After graduating from a University lawyers have been taking one more exam.
After graduating from a University lawyers had been taking one more exam.
After graduating from a University lawyers will have been taking one more exam.