The Correct Answer: 'a'


In English grammar, the choice between using 'a' or 'an' before a noun depends on the sound that follows the article. The indefinite article 'a' is used before words that begin with a consonant sound, while 'an' is used before words that begin with a vowel sound.


In the given sentence, "There is _____ bridge over the river," we need to determine the correct article to fill in the blank. The word "bridge" starts with the consonant sound /br/, which is why the correct answer is 'a'.


When deciding between 'a' and 'an', we focus on the sound rather than the actual letter at the beginning of the word. In this case, the sound that follows the article is /br/. Since /br/ is a consonant sound, 'a' is the appropriate choice.


If the word had started with a vowel sound, we would use 'an' instead of 'a'. For example, "There is _____ apple on the table." In this case, the word "apple" begins with the vowel sound /æ/. Therefore, the correct answer would be 'an'.


There are a few exceptions to the general rule of using 'a' before consonant sounds and 'an' before vowel sounds. These exceptions occur when the initial letter itself has a different sound than expected. For instance:
- "There is _____ university nearby." Here, the word "university" begins with the vowel letter 'u', but it is pronounced with a consonant sound /juː/. Therefore, we use 'a' instead of 'an'.
- "There is _____ honest person." The word "honest" starts with the consonant letter 'h', but it is not pronounced as a separate sound. Since the following sound is a vowel sound /ɒnɪst/, we use 'an' before "honest".


In summary, the correct answer for the given sentence is 'a' because the word "bridge" starts with a consonant sound /br/. Remember to consider the sound that follows the article when deciding between 'a' and 'an'.