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: Ropes are made from vegetable fibres each of which is only between two and four feet long, and the first process is to comb these fibres out in a long, even ribbon, as shown in an exaggerated form in fig. 6-1.
A:
Ropes