Ok, I got this question from my teacher "What will we be in the next 5 years", but I am not sure whether it means "What will we become in the next 5 years"
So, if someone says "What will we be in the next 5 years", then can we answer "We will be doctors in the next 5 years" or "We will become doctors in the next 5 years"
Whether you're talking about humanity, or an individual, the common and natural expression of this question that your teacher is grasping for is:
Where do you see us in five years?
or
Where do you see humanity in 5 years?
For an individual:
Where do you see yourself in five years?
This the common way of simply posing the question of what an audience predicts the future state of something to be. So if your teacher is referring to humanity, give him your opinion on what you think the state of our species will be in the next 5 years. For example:
Question: Where do you see us in five years?
Answer: Right in the middle of world war three.
Question: Where do you see yourself in five years?
Answer: Hopefully retired and sipping some fruity alcoholic beverage with an umbrella in it on a sunny, sandy beach.
As a side note, this is an excellent question. The reason is that this expression is very common and understanding it is important. This is a common interview question when seeking a job and will almost certainly be phrased exactly as a describe here, so understanding it is important.
I am sure your teacher meant "What will we become in the next 5 years" by saying "What will we be in the next 5 years".
But it sounds a bit unnatural to me. I would rather say:
What will we [have] become in 5 years?
or
What will we be 5 years later / 5 years from now?
Short answer:
Yes and both are completely natural-sounding. (source: native speaker) ("What will we become in five years?" also is natural and means the same thing.)
They mean almost the same thing. However, "What will we be?" is a little more general than "What will we become?" "Become" indicates a change. Using the word "be" allows for your answer to be something you already are right now.
In other words, you might answer, "We will be doctors," or "We will become doctors," or "We will be students." But since you're a student right now, you wouldn't say, "We will become students."
If it's a mixed group (some are students, some are not), you could use a qualifier, such as "We will ALL become students." That statement would mean that some of us are students currently, but those who aren't will become students.
Though you can use 'will be' or 'will become' interchangeably, there's a slight difference between these phrases.
Both the phrases are indicative that you will be in the state of being doctors, but the latter also has the overtones of your working towards achieving the said state.
