All Students preparing for Grade exams are recommended to use the Hofnotes on-line training pages to practise for the aural tests.
At higher grades you must be able to discuss with the examiner musical features such as texture, form, style, and period of a piece of music. My own web pages to help with these parts of the test at Grade 5+ and at GCSE are available here!
Do 
tonic
Ti 
leading note
La 
submediant
Sol 
dominant
Fa
subdominant
Mi 
mediant
Re
supertonic
Dotonic