Many thanks!By "ei" you appear to mean what we called the letter "a" (as in ABC).
Make has the same sound, but estimate only has this sound when it is a verb (e.g. Can you estimate the distance between Beijing and Hong Kong?).
But in Can you give me an estimate? the stress is on the first e and the "ate" does not sound like eit.
As i am Chinese, i can feel clearly there is an obvious difference between the "ei" in Beijing and "ei" in English. In Chinese, "ei" is a single syllable. But in English, I guess "ei" is a double syllable, right?I think the English sound that you are talking about has a strong resemblance to the "ei" of "Beijing".
OK. So it is actually a single syllable. But if i treat it as a single syllable, i would feel confused about, for example, "hit" and "hate". How stupid i am...Yes and no. The sound is actually a combination of a long 'e' sound, followed, without any pause or separation, by a short 'i'.
It makes a single syllable, distinct from (for example) say it or paying, where the same two sounds are used but divided into two syllables.