We can use formulas to model real-life situations. For example, the formula for calculating speed is speed = distance ÷ time. It is possible to calculate the speed, distance or time if you have the ...

A relative clause can be used to give additional information about a noun. They are introduced by a relative pronoun like 'that', 'which', 'who', 'whose', 'where' and 'when'. For example: I won’t ...