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.

Example Input: Furthermore, cable-laid rope, being more solid in construction, is more resistant to chafe and does not absorb water so readily as hawser-laid rope.
Example Output: cable-laid rope

Example Input: General characteristics.
Example Output: General characteristics.

Example Input: The sternsheetsman has to tend it.
Example Output:
The sternsheetsman