The meaning is broadly the same, but the sentences are not always applicable in the same circumstances.
“I'm sure he will make a good teacher” implies that he is currently not a teacher, and that when (or if) he becomes a teacher, he will be a good one.
“I'm sure he will be a good teacher” is similar, but applies to a definite point in time, whereas “will make” applies to an unspecified (and possibly hypothetical) future time.
“I'm sure he will become a good teacher” implies that he is currently not a good teacher, either because he is currently not a teacher, or because he is currently a bad teacher.
I'm sure he will make a good teacher, if he decides to quit his office job.
I'm sure he will be a good teacher. Let's hire him for the next term.
I'm sure he will become a good teacher, after a few more years' experience. Right now he's mediocre.
Some examples in the wild:
signs your boyfriend will make a good husband [The marriage will turn him into husband, and the question is whether he'll turn into a good husband or a bad husband.]
ways to tell if he'll be a good husband [Same question as the previous one really, but phrased differently. After the marriage happens, he will be a husband; will he be a good one or a bad one?]
will my boyfriend become a good husband? [Here, means the same as the previous two.]
Separate or stay? Is there a chance he'll become a good husband? [Here, he is already a husband, but not a good one.]
The nuances can change if you add a time complement.
I'm sure he will make a good teacher in the fullness of time. But right now, he's mediocre.
I'm sure he will become a good teacher when he completes his education degree.
“Make” carries a sense of achievement, whereas “become” sounds more passive.
In the past tense, the implications are somewhat different for make. “He made a good teacher” makes me think that he is no longer a teacher.
American native English speaker here. My gut check says that for the first pair, there is a extremely mild, extremely subtle difference in each case. They are sufficiently interchangeable, that even I, who am pretty big on subtle distinctions, think you can get away with exchanging them freely.
I am from China.
I come from China.
If I use the first formulation, I am possibly stating a perfectly neutral fact. It may be in response to a question about where I'm from.
But there's also a possibility that I am making a causal statement about why I am the way I am or why I see the world the way I do.
If I use second formulation, it is guaranteed to be the non-neutral connotation. It's never just a statement of fact, it's a statement of identity and culture and it's in a context where it's explanatory and causal. "I come from X, and the way we do/did things there is...." It means something like "who I am arises out of my belonging to the culture of X."
Additionally, the word "come" implies "somewhere not here" -- after all, to have come here you must have come from somewhere -- in a way that the version without doesn't. So in the question forms,
Where are you from?
Where do you come from?
the first is neutral in assumption as to whether or not the person asked is from here or elsewhere. The second implies, "Since you're not from here, where are you from?"
Because of that implication, "Where do you come from?" can be either more or less polite than "Where are you from?", depending on context -- particularly on whether or not the person asked has identified themselves as being from somewhere else. Asking someone who has identified themselves as from elsewhere where that elsewhere is is considered to be showing a polite and even flattering interest in them. Asking someone who has not so identified where they came from -- when they might have been born right here -- can be tantamount to calling them a foreigner, and suggesting they are unwelcome.
Best Answer
Okay then, I'll base my own answer simply on an analysis of the currently accepted answer.
The key sentence in the accepted answer (I admit that you are right suggests that the speaker wasn't agreeing with the second person's opinion but now admits or accepts openly that the second person is right) is simply wrong.
I will concede that 'admit' is admittedly the basis of the definition of 'concede'. But I will not admit that 'admit' itself necessarily implies the existence of a prior dispute. 'Concede' does carry that implication, but the difference between them is that 'admit' does not.
If you appear in a criminal court, you will be asked, firstly, to enter a plea: to plead guilty or not guilty, to state whether or not you admit the charge. The court will ask this on your first appearance before it, even though you have not previously had an opportunity to deny the charge. At this first hearing you can only either admit or deny it. If you deny it, then at a subsequent hearing you might change your mind and opt to concede defeat by changing your plea.
'Admit' does imply some consideration has taken place before speaking out, but it does not carry an additional implication that the speaker has disputed the facts prior to speaking. To maintain the fictional court setting: it is possible to admit the charge at the first hearing, by pleading guilty, an admission necessarily not requiring that you had disputed your guilt previously, since the charge had never previously been put to you.
There is nothing to concede, if you initially do plead guilty, since concede does carry an implication: namely that the speaker had previously made a false - or, at least, an inconsistent - statement (had, for instance, previously entered a plea of 'not guilty', knowing it was not true).
'Concede' implies a change of mind. 'Admit' only implies a making-up of one's mind. The distinction is between making a decision and changing a decision once made.