University College London's Excellent Online Grammar Resource

Having trouble revising from books? Try these interactive exercises in the following order:-

Nouns - P1; Determiners - P2, P3; Verbs - P1, P2, P4, P6, P7; Adjectives - P1, P3, P5; Week 4: Adverbs - P1, P2; Prepositions - P1; Conjunctions P1, (P2 if you're keen); Sentences - P5 (P2 if you're keen)