Pronunciation: /æt/ɒn ˈsʌmwʌnz ˈdɔːrˌstɛp/
noun a person, place, thing, or idea. In this case, 'doorstep' is a noun referring to the area in front of someone's door.
A1 There was a package left on someone's doorstep.
A2 The stray cat appeared on someone's doorstep looking for food.
B1 The mysterious letter was found on someone's doorstep early in the morning.
B2 The unexpected visitor arrived on someone's doorstep unannounced.
C1 The journalist found crucial evidence on someone's doorstep implicating the suspect.
C2 The politician's scandal was exposed when incriminating documents were left on someone's doorstep.
pronoun a word that can function by itself as a noun phrase and that refers either to the participants in the discourse (e.g. I, you) or to someone or something mentioned elsewhere in the discourse (e.g. she, it). In this case, 'someone's' is a possessive pronoun
A1 The package was left on someone's doorstep.
A2 I found a stray kitten at someone's doorstep.
B1 The mysterious package appeared on someone's doorstep overnight.
B2 The note left at someone's doorstep was written in a foreign language.
C1 The unexpected visitor on someone's doorstep turned out to be a long-lost friend.
C2 The news of the scandal broke on someone's doorstep, causing a media frenzy.
preposition a word that shows the relationship between a noun (or pronoun) and other words in a sentence. In this case, 'at' and 'on' are prepositions indicating location.
A1 The package was left on someone's doorstep.
A2 I found a stray kitten on someone's doorstep.
B1 She was surprised to find a letter on her doorstep.
B2 The unexpected gift on someone's doorstep brought a smile to their face.
C1 The mysterious package on someone's doorstep turned out to be a clue in the investigation.
C2 The politician found a protest on their doorstep demanding change.
formal The package was left at someone's doorstep by the delivery person.
informal I found a stray cat on someone's doorstep this morning.
slang I can't believe he showed up on her doorstep unannounced.
figurative The opportunity to start a new career landed on his doorstep unexpectedly.
at/on someone’s doorstep
at/on someone’s doorsteps
more at/on someone’s doorstep
most at/on someone’s doorstep
is at/on someone’s doorstep
will be at/on someone’s doorstep
has been at/on someone’s doorstep
is being at/on someone’s doorstep
at/on someone’s doorstep
at/on someone’s doorstep
to be at/on someone’s doorstep
being at/on someone’s doorstep
having been at/on someone’s doorstep