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.

[Q]: The length of a rope is measured in fathoms.
[A]: The length of a rope


[Q]: Manila rope.
[A]: Manila rope


[Q]: When made of manila or sisal, the fibres of the rope are treated with a rot-proofing solution during the first stage of rope-making, when the fibres are being combed into ribbons.
[A]:
the fibres of the rope