Choose the correct article for the blank: 'The battalion had to march through ____ hot sand of the desert.'
Choose the correct article for the blank: 'The battalion had to march through ____ hot sand of the desert.'
The phrase 'of the desert' makes 'hot sand' a specific, particular thing being referred to, so the definite article 'the' is used.
Re-check your working by substituting the answer back into the original question.