* Read the question carefully to identify what the question wants.
* If patterns and trends are identifiable it suggests a relationship
between the two variables as represented on the axes.
* Describe the patterns shown by the graph; refer to the gradient and
choose the appropriate words/phrases, for example rose/fell gradually,
sharply, levelled out, rapidly, reached a peak at, fluctuates ... etc.
* Always quote figures to support statements/interpretations by using the
data-read values, give rates etc.
