Why are there 3 different ways to pronounce “oo”?

Question

My German colleagues were laughing at the way I pronounce google, and it led to a discussion.

• With words like google, yahoo, poodle and loose, the oo has a sound similar to the German ü sound.

• With words like good and book, it is more similar to how Germans pronounce a oo sound.

• For words like door we are not sure if that is the same or different.

The Germans want to know what the pronunciation rules are so they can improve their English. I am guessing that there are no rules, and the pronunciation possibly comes from the original language that the word comes from.

Are there any rules? Is there any reason why there are two different pronunciations? Can non-native speakers work out the correct pronunciation by looking at the other letters in the word or the etymology?

Answer 1

I'd say that your German colleagues are mishearing the English pronunciations.

The German letter ü makes the sound [y], which does not occur in English.

The words loose, poodle, food, and most other words with oo have the vowel [u], which is usually spelled u or uh in German. Historically this is a long /o/ sound that was written with "oo", the pronunciation of which has shifted to [u] as a result of the Great Vowel Shift.

Some words with oo have instead the vowel [ʊ]: good, hood, book. There is no rule that predicts which words have this pronunciation, so you have to memorize it. The [ʊ] sound occurs in German as an allophone of /u/ in closed syllables. The vowel [ʊ] is shorter, more lax, and slightly centralized relative to [u]. This sound also tends to come from an older long /o/, though the reasons for this split are complicated and obscure.

A very small number of words with oo are pronounced with an [o] vowel: door, floor. These words always end in r, because the final r colors the preceding vowel. This is the same sound that is spelled o or oh in German.

Answer 2

Actually, I'd say that in "google" or "yahoo", "oo" sounds more like the German "u" rather than "ü". There's no "ü" sound in English really -- that I can think of.

The difference between "google" and "book" is more that "book" is a very short "oo" sound (so a German "u", but very short) whereas "google" and "yahoo" are long "oo" sounds. "door" is entirely different, in that it is pronounced more like the "o" in "Dortmund".

I'd say the general rule is that "oo" is a long sound, and "book" and "door" are exceptions to the rule.

Another exception is the word "good", which also has a short sound like in "put", "could" and "should".

Like @Al suggested in his comment, there's also "cooperate", which is pronounced like "co-operate", as if the two "o"s where distinct.

Answer 3

Relating to the "why" part of the question, the answer is very complicated and there is no compact set of answers, therefore there are no hard and fast rules.

The words that have what we call the "short oo", such as "book", "hook", etc. originally came from either the German un-dotted "u" ("buch"), which has a similar pronunciation somewhere in the area of the way we pronounce "pull", or from "o" ("hoken") and a little extra influence, possibly through feedback via the Dutch branch of the Germanic family ("hoek").

Words with the long "oo" as in "pool" and "cool" are evenly split between German "u" (these words would have originally had a "short oo" but evolved with time and dialect), German "uh" (which usually has the "ooh" pronunciation), and French "ou" (again nearly identical to a "long oo"; "pool" came from "poule", and "poor" was originally the Old French "poure" which in the French language was further influenced by Latin to become the modern "pauvre").

Words with the "oh" sound were either influenced by the "Great Vowel Shift", or have become more relaxed in pronunciation with the rise of American regional dialects. Most Americans would pronounce "poor" and "moor" the way most B.E. speakers would pronounce "pore" and "more". Words like "door" were influenced towards [o] very early in their life as the proto-Germanic "dur" and Old French "porte" met in Saxony and Briton to form the old English "dor".