Pilfered is a verb. It shows what the subject (thief) does.
The children were muffled up against the wind and snow. The sound of the orchestra was muffled by several closed doors between the concert hall and the corridor where I was standing.
The thief was scared as the knight brandished his sword=P
The ticket was valueless if used outside the store.
Yes, an exclamation mark is a type of full stop, so it should be followed by a capital letter. If the sentence is direct speech and followed by the words 'she exclaimed' or similar, it would be followed by a lower-case letter. 'She had the cheek to say that Peter was a thief! He soon put her right.' 'The car swerved up onto the pavement, narrowly missing my mother. "That car is going to crash into the wall!" she gasped.'
He knew that he'd been caught but he decided to brazen it out.
Verb
Verb 3====D - - -
Pip pilfered bread and other bits of food from his sister's kitchen to feed the man in hiding.
Parts of speech are determined by the use of a word in the sentence. Many words can be several parts of speech. I can't tell if you're asking about part of a sentence, or the name of a story or poem. For instance, the word "lighting" can be used as a noun, or a verb, and perhaps an adjective. The word "the" is usually an article. The word "thief" is usually a noun.
Jewels, money or other valuables taken by a thief.
The thief got away. The thief was caught.
It was the thief's partner that ratted him out to the police.
The cast of The Actress and Her Jewels - 1913 includes: Bobby Burns as The Thief Mae Hotely as Dottie Dare George Reehm as The Newspaper Man
The fog rolled in like a thief in the night.
The thief stole a purse from the unsuspecting woman on the busy street.
He was a thief, but got away with the crime.
ex. "The thief stole the burger in the middle of the night."