1.Past Simple Tense: The use of the past simple tense ("did", "was", "were") effectively describes habitual actions in the past, which is appropriate for the context of the question.
2.Complex Sentence Structure: The sentence "Completing my assignments before going to bed was crucial, and my parents were always there to assist me with challenging subjects" uses a compound sentence structure, connecting two related ideas with "and", showing the ability to construct complex sentences.