Unit 2
Lessons 2-3
Student’s Book pages 19-20
GRAMMAR
Modal verbs of possibility: must, might, could, can’t.
● We use various modal verbs to talk about degrees of certainty and uncertainty and to speculate about possibilities and impossibilities.
● We use must to talk about relative certainty.
It must be diamond!
There must be some cheese in the fridge.
● We use could to talk about possibility, including strong possibility or probability.
It could be someone who looks like her.
It could be amber. Amber has many different colours.
● We use might to talk more speculatively about things about which there is less certitude, only some degree of possibility.
It might be ruby because it is a hard precious stone.
She might be at the library. She always goes there after school.
● We use cannot (can’t) to talk about impossibility or negative certainty.
It can’t be amber because amber is found in northern Europe.
Yes, it can't be emerald because emeralds are green.