You are given an English sentence with a blank, and you need to predict the missing word. After completing, the whole sentence should be gramatically correct and non-ambiguous.

Ex Input:
had retired in haste to his club where he was chatting with some friends upon the events which served ____ a subject of conversation for three fourths of that city known as the capital of the world at the precise time when madame danglars dressed in black and concealed in a long veil

Ex Output:
as

Ex Input:
but no on reflection the procureur was not a merciless man and it was not the magistrate slave to his duties but the friend the loyal friend who roughly but firmly cut into ____ very core of the corruption

Ex Output:
the

Ex Input:
and believed firmly in her daughter's innocence and fidelity to the paternal roof she listened at eugenie's ____ and hearing no sound tried to enter but the bolts were in place madame danglars then concluded that the young girl had been overcome with the terrible excitement of the evening

Ex Output:
door