In French, objects have specific genders, either masculine or feminine, and can't be used randomly before a noun. As an example, the french word for table (which is also "table") is a feminine word, therefore you should refer to it as La table, and not Le table.
If you doubt the gender of an object, try using websites like www.wordreference.com to translate it from English to french, and get the word's gender.
See? When in doubt remove the e and it's masculine or if you are like the French and have a habit of rolling around the virtues of femininity with your tongue (ever hear of French kissing?) then just keep adding an e to make the words feminine. :)