Don't say tenks or thenks but thanks.

This is a mess of pronunciation characters.

"rat" [r\{t]
"ran" [r\{n]
"rank" [r\eNk]

"bat" [b{t]
"ban" [b{n]
"bank" [beNk]

"sit" [sIt]
"sin" [sIn]
"sink" [siNk]

"let" [lEt]
"lens" [lEn(d)z]
"length" ["leNkT]

>>North American English has gone thru a not insignificant amount of vowel changes and several of those involve raising<<

Could you explain what's that raising stuff all about? I've heard of Canadian raising, but what exactly is that?

<<Could you explain what's that raising stuff all about? I've heard of Canadian raising, but what exactly is that? >>

Well in certain environments (and in certain dialects--some are restricted to a region or two while others are widespread in North American English) certain historical or underlying front lax vowels in English are raised higher in the mouth in various forms of North American English.

Here are some (but probably not all) examples off the top of my head:

--"-eg" raising and tensing from historical or underlying /Eg/ to [e(I)g]. Thus for such speakers (like myself) "egg" has the same vowel as "vague," not "bed."

--"-ag" raising and tensing from historical or underlying /{g/ to [e(I)g]. Thus for such speakers (I personally do not have this but it's common in the Northern Midwest and parts of Canada and the Pacific Northwest amongst perhaps a few other places) "bag" has the same vowel as "vague," not "bad."

--"-ang" raising and tensing from historical or underlying /{N/ to [e(I)N]. Thus for such speakers (widespread in North America, tho not everyone has it) "bang" has the same vowel as "bake," not "ban."

--"-eng" raising and tensing from historical or underlying /EN/ to [e(I)N]. Thus for such speakers (I have this but not everyone does) "length" has the same vowel as "lake," not "lend."

-"-ing" raising and tensing from historical or underlying /IN/ to [iN]. I have this but this is a relatively recent change and outside of places like California and maybe a few other pockets this is not widespread yet. However its development is not surprising since it conforms to the raising and tensing of the other front vowels in the same environment. As someone who has raising and tensing of "-ang" "-eng" and "-ing" I have had this entire phonological change of:

lax front vowel--> raising, tensing/ ___ + /N/

completed in my speech. Who knows if it will spread or if it does how many decades it will take before it's completed. Anyway, for such speakers
"king" has the same vowel as "keen," not "kin."

-"-ezh" raising (as in "measure" or "pleasure") from historical or underlying /EZ/ to [e(I)Z]. I don't have this and it seems somewhat restricted to some parts of the Midwest and West but I've met people with this feature. For such speakers the first vowel in "measure" is the same as the one in "made," not "met."

If you're interested in more visual information I made a chart of these vowel comparisons between my speech, my friend originally from Seattle, and conservative General American here:

http://www.langcafe.net/viewtopic.php?t=286

Also notice that all these changes apply to instances of lax front vowels before /N/ only within the same morpheme and not across morpheme boundaries. Thus, "ink" raises to [iNk] for me but "income" doesn't since it's really analyzed as "in + come." Thus I have different vowels for "ink" and "income":

"ink" [iNk]
"income" ["Ink@m]

"ban" [b{n]
"ban cookies" [b{N "k_hUk_hi:z]
"bank" [beNk]

"ten" [t_hEn]
"ten kids" [t_hEN k_hI:dz]
"length" [leNkT]

I just made an audio recording illustrating what I was talking about. I read off the list of the words I provided on the Langcafe link. Here's the recording:

http://media.putfile.com/kirkraising5-24

<<<Yeah I don't rhyme "Thames" (which rhymes with "hems") with "thanks." For me the vowel in "thanks" and "tanks" is the same as the one in "takes." My pronunciation: ...

At least here in California nearly everyone has the same vowel in "take" and "tank." Many (such as myself) also have the same vowel in "lake" and "length" and "sink" and "see." >>>

Wow, Kirk! I'm actually very surprised by all this. Most of those samples you gave don't match my pronunciations, nor do they sound like what I hear on a regular basis from the people I encounter down here. There is this one lady on our local morning newscasts (originally from Lodi) who sounds pretty standard to me, but every once in awhile she'll pronounce a word that'll strike me as odd, like "eyg" for egg "beyg" for "beg" and "mayzhur" for "measure".

<<Wow, Kirk! I'm actually very surprised by all this. Most of those samples you gave don't match my pronunciations, nor do they sound like what I hear on a regular basis from the people I encounter down here. There is this one lady on our local morning newscasts (originally from Lodi) who sounds pretty standard to me, but every once in awhile she'll pronounce a word that'll strike me as odd, like "eyg" for egg "beyg" for "beg" and "mayzhur" for "measure".>>

Really? That's odd because pretty much everyone I know from LA (that's my age) also has the raising I do. I've noticed no regional differences (linguists have documented these phenomena and they've pointed out they show up in the Bay Area, too). In fact a good friend of mine is from LA and her favorite color is "pink," which she definitely pronounces "peenk" like I do. One thing I should note is that almost no one notices these things consciously but in listening to people around me people definitely do it.

Anyway, as I said before I do have "eyg" and "beyg" but not "mayzhur" which sounds odd to me.

You all do not speak correct. As the way you respell in pronunciation, it seems you do not have any knowledge of how to speak appropriately.

Don't criticise too much but learn English which I don't read you all do.

Bye-bye!

An alternative is "Ta".

A better alternative is "or". Often found in cryptic crosswords.