Teacher: 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.
Teacher: Now, understand the problem? If you are still confused, see the following example:
Rope and its Usage
Solution: Rope
Reason: The word 'Rope' is the key subject here, while Usage is a property of Rope.

Now, solve this instance: Commercially manufactured manila ropes over 2 inches in circumference and complying with the specification of the British Standards Institution are identified as follows: Grade I, 'Special', one black rogue's yarn in three strands; Grade II, 'Standard', one black rogue's yarn in two strands; Grade III, 'Merchant', one black rogue's yarn in one strand.
Student:
Commercially manufactured manila ropes over 2 inches in circumference and complying with the specification of the British Standards Institution