Teachers, be on your guard. Don't be caught in the euphemism trap because it could seriously damage your career. They are often used by headteachers proposing something to your disadvantage.
So, take care if a head offers you a "developmental opportunity". What this means is that you will be expected to do a job - usually one that nobody else wants - for no money and a promise that, sometime in the future, you will be rewarded.
Also, watch your step if you are asked to take a "challenging class"
because the head values your teaching ability. This class will exhibit appalling behaviour, will be impossible to teach and will have made previous teachers ill with stress. Every supply teacher who encountered this class probably left immediately.
Be alert if a head says they know how difficult it is to teach after the lunch break because the pupils are wound up. They are not being altruistic.
Their concern is code for: "Let's shorten the lunch hour as the senior staff on duty cannot control the pupils."
While you then try to cram your lunch into a shorter time, senior staff can have a leisurely lunch while you are teaching in the afternoon.
Excuses for asking you to cover classes are interesting. "Sorry, I can't get a supply," often means heads have not really tried (or don't have the budget), but they hope the apology will assuage your anger.
The head also wants to be bottom of the expulsion league table. So, if you are asked to keep a portfolio of evidence, be suspicious. Ostensibly, it will be to keep check on a pupil's progress. However, what it really means is: "We do not trust you to teach or assess this pupil properly. We will never check the portfolio, but we want documentary evidence that you are doing what you say you are doing."
Similarly, the question: "Are you sure the curriculum is appropriate?"
should be treated with suspicion. What is really meant is: "We have serious concerns about the behaviour in your class and other lessons are being disrupted. We don't care what you do as long as you shut them up."
It is not as if the lesson content will miraculously turn the class from devils into compliant angels.
If you are faced with "parents have complained", this probably means a parent with an average child is concerned because the science homework you set did not challenge their budding Einstein.
Yes, in education many people speak with a forked tongue - but at least you will be prepared.