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.

Weights and breaking strengths can be taken as being the same as those of cordage of similar size, material and normal lay.
Weights and breaking strengths

Rot-proofing neither weakens the rope nor increases its weight, but makes it watertight to the extent that, when wet, it absorbs hardly any water and is nearly as light and as easily handled as when it is dry.
Rot-proofing

It is used in the Royal Navy only for small lines and small stuff.

It