In this task you are given a sentence. You must judge whether subject of the main clause is singular or plural. Label the instances as "Singular" or "Plural" based on your judgment.
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Question: His concentration since Iseo left Compostela fell completely to his training.

Answer: Singular


Question: My sneakers let off an admittedly adorable perky sound as I marched back over to the sidelines.

Answer: Plural


Question: The pirates organized themselves into groups at the bow and stern and lined the deck, two at each cannon.

Answer:
Plural