COMMON ERROR 7: LACK OF AGREEMENT WITH PRONOUNS AND POSSESSIVE ADJECTIVES

Pronouns (e.g. he, they) and possessive adjectives (e.g. my, your) must agree in number and gender with the words they refer to.

WRONG Any building will deteriorate if they are not painted regularly, and their maintenance is neglected.
’Building’ is singular and the words ‘they’ and ‘their’ are plural.

RIGHT Any building will deteriorate if it is not painted regularly, and its maintenance is neglected.
’Building’, ‘it’ and ‘its’ are all singular.