how to pronunce /ths/?

like months, depths, lengths, just pronunce them like "monts" "depts""lengts", just skip the "h" sound?

Nick, you may be amazed that these words actually have multiple forms of pronunciations in their plural forms.

month: 'm&n(t)th, in its plural form: 'm&n(t)s or 'm&n(t)ths

length: in its plural form: 'le[ng](k)ths, 'len(t)ths, or 'le[ng](k)s

depth: 'depths, or 'dep(t)s

You do not particularly skip the "h" sound.

<<Nick, you may be amazed that these words actually have multiple forms of pronunciations in their plural forms.

month: 'm&n(t)th, in its plural form: 'm&n(t)s or 'm&n(t)ths

length: in its plural form: 'le[ng](k)ths, 'len(t)ths, or 'le[ng](k)s

depth: 'depths, or 'dep(t)s

You do not particularly skip the "h" sound.>>

so what do you mean by (t) (k)?

Stan means that in some dialects, a K or T sound gets inserted into the word to make it easier to connect all of the consonants that are being strung together in "lengths" and "depths". Even we native English-speakers have to find ways to deal with them! ;)

I still can't understand that, can someone put it another way?

It's hard to put an N, a G, a TH, and an S together with no intervening vowels. "Lengths" is hard to say as written, especially in rapid, everyday speech, so people often say something that sounds like "lenkths".

Other people will modify it in a different way: "lent-ths". I have heard both variations.

The main thing is that in practice, certain consonant clusters tend to either be reduced, assimilatd, or have extra epethetic consonants inserted into them to make them more pronouncable by even native speakers. These are just two common examples of such, but such include, for example:

/NT/ -> [NkT] or [NtT]
/Ts/ -> [s:]
/NTs/ -> [Nks:] or [Nts:]
/nT/ -> [ntT]
/ns/ -> [nts]
/nTs/ -> [nts:] or [ntTs]
/Dz/ -> [z:]
/skt/ -> [st] (especially in "asked")
/sts/ -> [s:]
/kts/ -> [ks]
/kt/ -> [k]
/np/ -> [mp]
/nb/ -> [mb]
/ndz/ -> [nz]

Just in case anybody else finds it useful, I've assembled a short list of examples of words in which these assimilations could occur (it actually took much longer than expected).

/NT/ -> [NkT] or [NtT]
length
/Ts/ -> [s:]
both sides
/NTs/ -> [Nks:] or [Nts:]
lengths
/nT/ -> [ntT]
tenth
/ns/ -> [nts]
vengeance
/nTs/ -> [nts:] or [ntTs]
tenths
/Dz/ -> [z:]
smooths
/skt/ -> [st] (especially in "asked")
risk taken
/sts/ -> [s:]
last summer
/kts/ -> [ks]
perfects
/kt/ -> [k]
perfect
/np/ -> [mp]
brainpower
/nb/ -> [mb]
green belt
/ndz/ -> [nz]
grayhounds

I found this at http://eleaston.com/pr/sl-pat-th.html, take a look, please

In careful speech, I pronounce months, depths, and lengths as [mʌnθs], [dɛpθs], and [lɛŋθs], respectively. However, in rapid speech, I pronounce them as [mʌns], [dɛps], and [lɛŋks]. The degree to which the former pronunciations slide towards the latter depends on circumstances; I note that usually there remains some trace of /θ/ in there, but it can be quite hard to hear (although I do feel myself articulating it).

Well,
It differs from people to people depending upon the society of residence, every language has this kind of stuffs and it's really confusing too. But who cares for whom??? We are self centered and speak & do of our wishes.

To Mxsmanic:
Why you pronunce lengths [lɛŋks] not [lɛŋs]?

<< Why you pronunce lengths [lɛŋks] not [lɛŋs]?>>

That's an example of an epenthetic consonant, which is basically a consonant which is added (but not necessarily present in the underlying phonemic level) to facilitate pronunciation. This is done quite commonly in languages thruout the world. Here's the article on epenthesis from Wikipedia:

http://en.wikipedia.org/wiki/Epenthesis