Yeah, if a Martian saw us using consonant clusters like “ghtt,” they’d think English was related to Klingon.
I was taught:
i before e, except after c,
when the sound is “ee”.
Which I think covers a few more cases, including seismologist, although not weird (but then weird should be weird, perhaps).
I am amazed that a question about the spelling of eighteen has now generated 42 replies!
I’m sitting here saying “make, make, make” over and over and apparently we pronounce it very differently. I hear only one vowel sound; the long A.
When you say make, Rickjay, pay attention to your jaw. As you pronounce the a vowel, do you feel it shifting up and your mouthspace reducing in size? That’s your mouth forming the second part of the diphthong, the ee part. For me, if I don’t let that happen, saying make comes out sounding like mack.
I can’t speak for RickJay, but no, I do not feel this when I say “make”, or even “ay” (long a) by itself, even a really long “ay”, like Fonzie.
When I pronounce it, it’s a diphthong, ending with a slight “y” type of sound. This link, if you scroll down to “English speakers tend to pronounce [e] with a diphthong,” shows the difference between the sounds with an audio link.
I can make (ha) myself say ‘mayeek’, but it’s not the natural way I would say it. It’s just one vowel for me.
It doesn’t sound like “mayeek,” though. Most American English speakers, in my experience, say it as a diphthong. It is analogous to the types of diphthongs you experience when you say “lie” and “boy,” except with a different initial vowel sound. Do “lied” and “toyed” to you sound like one vowel to you? If so, then you probably will interpret the “ay” in “make” as a pure vowel, when you are pronouncing it as a diphthong. It’s one of those pronunciation things that most people simply don’t notice. Did you check out the link above that has sound files demonstrating the difference between “é” and “ay”?
Now, there may be dialects of American English where “ay” is not pronounced as a diphthong, but the diphthong is the usual pronunciation.
I’m exaggerating the spelling for emphasis (I took linguistics, so I’m used to hearing the differences between sounds but I hate looking up the IPA symbols). When you say American, do you mean USA or North America? I’m Canadian, and pronounce it like the second example.
My jaw does not move, but my mouth space does contract. It has to, in order to mayeek 
the “k” sound. Does that mayeek it a dipthong? If so, it’s impossible to have a non-dithong “a” before a “k” sound.
When you say May, does your mouth contract at all?
For me, not at all. I can say “mayee” and my jaw moves back up during that, but again, it feels forced.
When I say “American,” I am referring to both General American and Canadian English.
When I say “make” there’s a slight “chewing” motion–maybe that’s what you mean by mouth space contracting. When I say “mék” (without the diphthong), the only contraction is in the back of my throat for the “k” sound. “Make” and “mék” are subtly different, and I doubt most English speakers even notice, as the two sounds are not distinguished in English. When I was learning Hungarian, the word for “blue” sounded like “cake” to my ears. And when I (or pretty much any native English speaker) said it, my Hungarian teacher would immediately correct me. It took me a little while to distinguish the vowel in “cake” from the vowel in kék. What I was saying was closer to what would be written as kejk in their language.
See, for me, there’s a slight lifting of the tongue to finish off the sound. So, if I try to purposely elongated, as if to say MAAAAAAAAAAAAAAAAAY, I don’t just cut off the airflow at the very end to finish it–there’s a little “y” type of flourish in the mouth to finish it.
Well see, that’s exactly what I do. My tongue is firmly planted on my teeth through the whole word. There’s no upward anything (tongue, jaw, whatever) when I say the word.
OK, then it does sound like, in fact, you say it as a pure vowel. This is not the usual way it is pronounced in North American English, though.
Both sound files here are for the pronunciation /meik/, with the diphthong /ei/. make - Wiktionary
This thread illustrates why I wish English in schools were taught by instructors who actually understood something about how language works; instead they fill heads with this long/short vowel nonsense. I doubt very much that Raygun99 pronounces “make” with a monophthong. Some diphthongs have shifted toward monophthongs in a few American dialects, but this isn’t one of them. [edit: I spoke too soon. There are a few examples. However, see wiktionary link for “standard” pronunciation]
Then again we’d certainly have fewer threads about pronunciation, spelling, and grammar. I kind of like those.
For hours of sound fun, you can hear diphthongs here. Diphthongs
Their main page has links to other kinds of sounds. Thanks to Omi no Kami for that link in another thread about English vowels: Why Are English Vowel Sounds so Similar? - Factual Questions - Straight Dope Message Board
No, to be honest. The long A is a consistent sound.
I live in Canada, perhaps it’s a part of our accent. There’s a definite difference between my accent and most Americans, who to my ears use far more dipthongs and slide from vowel to vowel in a way people here never do, depending on region. We must sound very clipped by comparison, as if we’re rushing to get on to the next word.
I do though. And it’s not like I’m not used to hearing the difference. By contrast, I would say that I use the dipthong under discussion in “mace”, as my jaw moves to make the “soft c” sound, while it stays still to make the “hard k” sound in make.
Diphthongs are often raised in Canadian English, and in the interior /eɪ/ sometimes ends up more like /e/.
Also just realized I wrote /meik/ instead of /meɪk/ in my previous post.
/eɪ/ really is not the best example of a diphthong. The so-called “long I” might be better. It’s usually /aɪ/ (lied) or /əɪ/ (light) for most USians, and I can’t think of any examples of monophthongization, although writing that means I’ll find one in a few minutes.