En los siguientes enlaces, encontrarás ejercicios para practicar los artículos:
http://www.ejerciciodeingles.com/ejercicios-distinguir-some-any-a-an/
http://www.grammar.cl/Games/Some_Any_A_An.htm
http://www.montsemorales.com/gramatica/SomeanyPDC.htm
http://www.time4english.com/aamain/school/e2ag1a.asp
http://www.bradleys-english-school.com/online/flashmultiplechoice/mc_aansomeany.html
http://suz.digitaleschulebayern.de/english/grammar/some1.htm
http://www.bradleys-english-school.com/online/MultipleChoice/aansomeany.html
http://www.englisch-hilfen.de/en/exercises/confusing_words/a_an_some.htm
https://www.ego4u.com/en/cram-up/vocabulary/some-any/exercises?09
http://www.focus.olsztyn.pl/en-grammar-articles-test-2.html#.WM51Pfk1_IU
http://www.isabelperez.com/some-any.htm
http://www.focus.olsztyn.pl/en-english-some-any-exercises.html#.WM51Tfk1_IU
http://www.english-grammar.at/online_exercises/quantifiers/quantifiers1.htm
http://www.folkuniversitetet.ee/harjutused/Beginners/SomeAny.htm
http://www.ejerciciodeingles.com/ejercicios-distinguir-some-any-a-an/
http://www.grammar.cl/Games/Some_Any_A_An.htm
http://www.montsemorales.com/gramatica/SomeanyPDC.htm
http://www.time4english.com/aamain/school/e2ag1a.asp
http://www.bradleys-english-school.com/online/flashmultiplechoice/mc_aansomeany.html
http://suz.digitaleschulebayern.de/english/grammar/some1.htm
http://www.bradleys-english-school.com/online/MultipleChoice/aansomeany.html
http://www.englisch-hilfen.de/en/exercises/confusing_words/a_an_some.htm
https://www.ego4u.com/en/cram-up/vocabulary/some-any/exercises?09
http://www.focus.olsztyn.pl/en-grammar-articles-test-2.html#.WM51Pfk1_IU
http://www.isabelperez.com/some-any.htm
http://www.focus.olsztyn.pl/en-english-some-any-exercises.html#.WM51Tfk1_IU
http://www.english-grammar.at/online_exercises/quantifiers/quantifiers1.htm
http://www.folkuniversitetet.ee/harjutused/Beginners/SomeAny.htm