- DOCTOR: You needn’t go on a diet; but you must eat sensibly and you mustn’t overeat.
- ZOO NOTICE: Visitors must not feed the animals.
- RAILWAY NOTICE: Passengers must not walk on the line.
- You mustn’t drive fast. There is a speed limit here.
- You needn’t drive fast. We’ve plenty of time.
- You needn’t strike a match. I can see well enough.
- You mustn’t strike a match. This room is full of gas.
- SCHOOL NOTICE: The lifts must not be used during the Fire Drill.
- You mustn’t wear that dress again. You look terrible in yellow.
- TEACHER: You needn’t read the whole book but you must read the first four chapters.
- You must cut down that dead tree or it will fall on your house.
- DOCTOR: You mustn’t take more than two of these pills at once. Three might be fatal.
- DOCTOR (to patient’s wife): If the pain has gone he needn’t take any more of these.
A Practical English Grammar (A.J. Thomson & A.V. Martinet) 