wǒ (or ě)
When is 我 pronounced as ě?
Haven't even able to find any examples.
I got email from grandricci.org:
The pronounciations you point out are presently not in use, indeed. They had been included in the dictionary fifty years ago by the first team because they were recognized by old dictionaries of that time or by the fanqie 反切 indicated in the Kangxi cidian. From a linguistical point of view, they are not wrong. But as they are not in use, in later editions of the Dictionary, the Association Ricci will have to make a choice between delete them or indicating their linguistic status.
As others have explained, ě is currently used in certain nonstandard dialects. You might be interested to know that ě is the expected pronunciation based on the regular sound changes that connect Mandarin to the Middle Chinese pronunciations recorded in rhyming dictionaries. Compare these words:
我: Mand. wǒ, MC nga, rising tone,
餓: Mand. è, MC nga, departing tone,
蛾: Mand. é, MC nga, level tone,
which had the same initial and vowel but different tones. The pronunciation wǒ is not expected purely from the historical evidence of old dictionaries. I'm not certain where it came from, but it could have been influenced by words such as
吾: Mand. wú, MC ngu, level tone.
What I've written so far isn't enough to prove anything, but hopefully it provides more context. Another interesting question might be "Why is 我 pronounced wǒ?" It appears to be a slang usage that became standardized because of the political and economic power of the regions it's used in.
In some regions in northern China, for instance, Shanxi Province, "我” is pronounced as ě. In fact, there is no point in learning this sort of pronunciation, for it is merely applied in dialect. And in these dialect systems, not only “我”, scores of Chinese characters' pronunciation and intonation are changed(compared to Mandarin), which is difficult for most people, including the Chinese.