My father bought . . . . . . . . H. M. T watch. . . . . . . . . watch is beautiful.

Use 'an' before words such as "hour" which sound like they start with a vowel even if the first letter is a consonant. Also use 'an' before letters and numbers which sound like they begin with a vowel, such as "H" or "8". First blank will take 'An'. As watch identity is known we will use 'the' in the second blank.