The neutral tone in Mandarin Chinese

Mandarin Chinese is a tonal language, meaning that the pitch contour of a syllable influences the meaning of that word. This is introduced in all basic textbooks, often even before the first chapter begins. Mandarin Chinese has four tones that are often introduced properly (with the exception of the third tone, which is often not described clearly at all).

The neutral tone in Mandarin Chinese

However, there is also a neutral tone which is sometimes glossed over.

It appears on reduced syllables and only appears in the second syllable in two-syllable words or in between full syllables, such as the middle of a three-syllable construction when the middle syllable has a grammatical function. An example of the first case would be 孩子 (háizi) "child; children" and an example of the second would be 对不起 (duìbuqǐ) "I'm sorry".

The neutral tone is not a fifth tone

This is not a fifth tone as some people claim, it's what happens when the tone is reduced or removed. That means that the basic characteristic of the neutral tone is that it should not keep the original tone of the character! It can be influenced by several things, but mainly the tone of the preceding character or the intonation of the sentence as a whole.

Even though some neutral tones can be pronounced in several different but correct ways, there is a default neutral tone that you should learn. The normal way of describing tone height in Mandarin Chinese is to use a scale from 1 to 5 where 1 is very low and 5 is very high.

To give you an idea how this system works, here are the standard way of writing the four full tones:

First tone (high, level): 55
Second tone (rising): 35
Third tone (low or dipping): 21(4)
Fourth tone (falling): 51
The default neutral tone should then be as follows after each of these tones:

After a first tone: 2 (low)

After a second tone: 3 (mid)
After a third tone: 4 (high)
After a fourth tone: 1 (very low)
It's not as complicated as it looks

This looks more complicated than it really is. In essence, the neutral tone falls except after a third tone when it rises. These are the only two things you need to remember, fine-tuning the height of the neutral tone will occur quite naturally by listening to natives and speaking with them. Do remember that the neutral tone is usually high after a third tone, though, since this produces a unique contour.

Intonation and the neutral tone

As I said in the introduction, the neutral tone is free to change according to the situation rather than depending on the tone of the syllable itself. The patterns I have given above work well as the default reading, but you should be aware that native speakers usually deviate from this depending on context. This is similar to intonation in English where we lower the pitch of statements and raise it for questions. This is true for Chinese as well, so a neutral tone in a question is likely to be higher than in a statement.

Finally, it should also be mentioned that there is a difference between fixed neutral tones (i.e. words that can only be read with a neutral tone and it would be wrong to read it with a full tone) and reduced syllables in normal phrases.

For instance, the 来 (lái) in 起来 (qǐlái) is often reduced to a neutral tone, but this doesn't mean that you absolutely have to read it with a neutral tone. How often these reduction occur depends largely on which type of Mandarin we're talking about. For example, in Taiwan, people reduce syllables much less than in Beijing.