Crises? What crises?

I was pleasantly surprised the other day because rather unexpectedly I found a good example of how the plural of the word crisis –which is spelled crises, as you probaby know- has to be pronounced. Again, this was in an old BBC4 programme I had downloaded years ago, and I thought it was a good opportunity to brush up on a case many Spanish speakers might not know or have forgotten.

The rules are the same for all words ending in –sis, so this also applies to the plural of terms such as analysis, basis, crisis, thesis, genesis, oasis, diagnosis, synthesis, prosthesis and emphasis, among others.

Before starting with the explanation, let’s listen to the recording:

 There’d been a series of crises in which the Republic seemed to have shown itself as corrupt, as weak, as divisive and so on… (Robert Tombs, BBC4).


First, the spelling rule:

  • Words ending in -sis make their plural in -ses, like this:

crisis/crises, basis/bases, analysis/analyses, etc.


Second, the pronunciation rule. There are two changes and a warning. The changes are:

  1. The /ɪ/ becomes //
  2. The second /s/ becomes /z/

For example:

crisis /ˈkraɪsɪs/ – crises /ˈkraɪsiːz/

basis /ˈbeɪsɪs/ – bases /ˈbeɪsiːz/

analysis /əˈnæləsɪs/ – analyses /əˈnæləsiːz/

The warning, I’ll write about later.


Now, let’s listen to the recorded example again:

 There’d been a series of crises.

The first change, the long // is very noticeable. Let’s listen to it again:  crises.

However, the second change, the /s/ turning into a /z/, is nowhere to be seen or heard. Why is it?

Here is when we have to talk about the warning: because voiced consonants become devoiced at the end of words if they aren’t followed by another voiced sound. This process is thoroughly explained in this article. So, in actual fact, the /s/ remains as it is (voiceless) unless it is linked to a following vowel or voiced consonant. In the example we’re analysing, the speaker makes a pause after the word crises, so he pronounces an /s/. If he had linked it to the following word, in, he would certainly have produced the voiced version of the sound, /z/.