TASK DEFINITION: In this task, you are given a sentence. You must find the primary subject in the supplied sentence. The output must be a sub-sequence in the sentence.
PROBLEM: Three hawser-laid ropes each of 120 fathoms, laid up together in the opposite direction to that of their own lay, will form a cable-laid rope, 100 fathoms in length.

SOLUTION: Three hawser-laid ropes

PROBLEM: Handling hawsers.

SOLUTION: hawsers

PROBLEM: Three strands so laid up constitute a hawser-laid rope, which is the type of cordage most commonly used.

SOLUTION:
Three strands