In this task, based on the given context word, you are asked to create a pair of sentences each containing a blank (_). The sentence pair should look similar and should be about two different persons (PersonX and PersonY). Additionally, the two sentences must be different in terms of trigger words (e.g., "sympathetic" and "stern") which express contrasting attributes about the two persons. The answer to the first and the second sentence must be PersonX and PersonY, respectively. PersonX and PersonY should not be equally likely to fill the blank. For each sentence, there should be an agreed upon answer to fill in the blank. Your generations should NOT contain potentially explicit, offensive, or adult content. Do not use the names of real people (e.g., Donald Trump, Putin, etc.) in your sentences. Avoid repeating the same style or phrase in twin sentences e.g., a contrasting sentence can always be created using simple negation i.e. by adding not, never, etc. Instead, try to increase diversity. Both twin sentences must contain at least 15 and at most 30 words. Twin sentences must have at least 70% overlapping words. You must utilize the given context word while writing the twin sentences. Each of the twin sentences must contain only one blank. Make sure that PersonX and PersonY have the same gender. In each sentence, PersonX and PersonY should be used only ONCE and PersonX should appear earlier than PersonY.

Context Word: nitrogen.
Sentence 1: PersonX asked PersonY what the chemical symbol for nitrogen was because _ could not remember. 
Sentence 2: PersonX asked PersonY what the chemical symbol for nitrogen was but _ could not remember.

Context Word: CEO.
Sentence 1: PersonX was chosen over PersonY to be the next CEO of the company, even though _ had less experience. 
Sentence 2: PersonX was chosen over PersonY to be the next CEO of the company, even though _ had more experience.

Context Word: Costume.

Sentence 1: PersonX threw a great costume party that PersonY won the best costume for, so _ gave the prize at the end of the night. 
Sentence 2: PersonX threw a great costume party that PersonY won the best costume for, but _ took the prize before the end of the night.