In literary criticism, close reading is the careful, sustained interpretation of a brief passage of a text. A close reading emphasizes the single and the particular over the general, effected by close attention to individual words, the syntax, the order in which the sentences unfold ideas, as well as formal structures.
Searched for a gold mine.
The answer is 'when driving'.
The whole meaning is misunderstood without the rest of sentence. He always smokes when driving - in this case every word is in a chain so we understand what every part means.
If you cut some words from a text it is not more than just a fragment...
In his comedies, Shakespeare is well known for the device of mistaken identity. Often in his plays, women dress up as men and nobody can see the difference, which creates the illusion of a mistaken identity.