The adverb only should be placed as close as possible to the word it modifies in a sentence. Consider the following two sentences:
Example 1: The band only sang five songs at the concert.
Example 2: The band sang only five songs at the concert.
Example 1 indicates that the band sang, rather than played, five songs. The sentence in Example 2 indicates that the band sang five songs, rather than eight or ten or any other number. There is a distinct difference in meaning. However, it is common for only to be misplaced in a sentence, making the meaning of the sentence ambiguous.
A similar error was made with the popular old song called “I Only Have Eyes for You.” The writers of this song would have made the message clearer by writing “I Have Eyes for Only You.” But then again, the song just wouldn’t sound the same had the lyrics been written to be grammatically correct. Regardless, when using only in your own speaking and writing, remember to place it as close as possible to the word you are modifying so the meaning of the sentence is clear to the audience.