Fill in the Blanks Exercício 1 - Lição 1Online version Exercício sobre os artigos indefinidos a/an by romilson gomes 1 1 ) A ou an ? a ) elephant b ) university c ) umbrella d ) ticket e ) VIP f ) honest man g ) half - hour lesson h ) one - hour lesson i ) useful book j ) SOS k ) X - ray l ) European m ) hand n ) underpass o ) unit p ) CD q ) exam r ) schoo l