Final answer:
The meanings of the words in parentheses indicate tireless energy (indefatigable), unable to be defeated (invincible), clear in thought or expression (lucid), irrational (dementedly), showy (ostentatious), and unaware (oblivious). Understanding these definitions helps in comprehending the sentences and contexts in which these words are used.
Step-by-step explanation:
Understanding the meaning of words within parentheses is essential for grasping the context of sentences. Here are the meanings tailored for the student's question:
Indefatigable means incapable of being tired out; not yielding to fatigue; tireless.
Invincible means incapable of being conquered, defeated, or subdued.
Lucid means easily understood; completely intelligible or comprehensible.
Dementedly means in a state of mental decline; insane or acting irrationally.
Ostentatious refers to a display meant to impress others; pretentious in display.
The children were oblivious to their teacher's wishes, meaning they were not aware of or not concerned about what was happening around them.
With these definitions, the student can better understand the words used in the sentences provided and improve their vocabulary skills.