TASK DEFINITION: Given a sentence, generate a most likely context or previous statement. The previous statement should be relevant to the given statement.
PROBLEM: It swings open revealing a stunned someone on her cellphone.

SOLUTION: Someone faces a door and knocks.

PROBLEM: Someone raises his arm to someone.

SOLUTION: People rush from the crumbling Temple.

PROBLEM: With someone and his sister, someone, on either side of him, someone slowly turns to face the gathering.

SOLUTION:
Someone strides between the rows and stands at the front.