April: April? May: May, June: June?

July: July, August: August? September: September

October: October, November: November, December: December?

Extended data:

January: plural: Januaries, abbreviation: Jan

February: plural: February, abbreviation: February

March: plural: Marches, abbreviation: Mar

April: plural: April, abbreviation: April

May: plural: Mays, abbreviation: may

June: plural: June, abbreviation: June.

July: plural: Julies, abbreviation: Jul

August: plural: August, abbreviation: August

September: plural: September, abbreviation: September

October: plural: Octobers, abbreviation: Oct

November: plural: November, abbreviation: November

December: plural: Decembers, abbreviation: Dec