My Grandfather, AKA "The Grandfather Passage", is one of the most common standard reading passages used to test an individual's ability to produce connected speech. If you are having a thorough speech evaluation, one of the last things the evaluator will do is hand you a paper containing block of text for you to read. There's a good chance that that text will be My Grandfather.

It was designed to contain almost all the English phonemes (by my count it's missing ʒ and the glottal stop). In this it is closely related to Arthur the Rat, a block of text used for studying accents and dialects. There are minor variations, but it goes something like this:

You wish to know all about my grandfather. Well, he is nearly 93 years old; He dresses himself in an ancient, black frock coat, usually minus several buttons; yet he still thinks as swiftly as ever. A long, flowing beard clings to his chin, giving those who observe him a pronounced feeling of the utmost respect. When he speaks his voice is just a bit cracked and quivers a trifle. Twice each day he plays skillfully and with zest upon our small organ. Except in the winter when the ooze or snow or ice prevents, he slowly takes a short walk in the open air each day. We have often urged him to walk more and smoke less but he always answers, "Banana oil!" Grandfather likes to be modern in his language.

The reading will be recorded and can be analyzed in terms of fluency, speed, spectrographic analysis, jitter and shimmer, and appropriate pitch changes. For all of these, and for any other qualities of speech that are being targeted, the goal is not perfection, but being sufficiently close to the norm. All human voices have shimmer and jitter, and would sound very odd if they didn't. Hesitations, self corrections, and pauses are common. This one of the reasons why the passage is so long, so that the clinician can get a sufficient amount of data that one or two errors wont mess up the results.

Having said this, My Grandfather is actually a pretty short piece. The other particularly 'famous' standard reading passage is The Rainbow Passage, which is about twice as long (although it also has a short version). On the flip side, researchers and clinicians will often take only a short segment of a passage to compare. For example, as a rule of thumb it should only take someone about two seconds to say the first line, "You wish to know all about my grandfather."

My Grandfather is also used as a sort of vocal 'Lorem Ipsum' for checking the sound quality of recordings, acoustics of buildings, and anything else where a random segment of speech is useful.

This particular version of My Grandfather came from The Audiologists' Desk Reference, By James Wilbur Hall and H. Gustav Mueller.