PS "oatmeal" is an uncountable noun. The Oxford online dictionary defines it as a "mass noun" http://www.oxforddictionaries.com/definition/english/oatmeal "I will buy (some) oatmeal in the shop." "oatmeals" would be wrong.

Here are some clues: a) uncountable nouns can exist without any article e.g. "Love is in the air". However, many uncountable nouns can also be used as countable nouns e.g. "The love of my life" "A love which will last forever" b) uncountable nouns are singular, so if you see a plural -s at the end, it is a countable noun (or an uncountable noun used as a countable one, like "love" above). c) These determiners only appear with countable nouns : a, an, many, those, these, few, a few, another, other d) These determiners only appear with uncountable nouns : much, little, a little. Because many uncountable words can also be used as countable nouns, it's really important to focus on the meaning. Articles and other determiners are never random or conventional - they always reflect the meaning. Think about the difference between "love" in my three examples. Each option was correct because I was expressing something different about "love" each time.

Bred is the past tense of breed. Oatmeal is a singular noun (breakfast) Oat = singular; oats = plura

Oat is a singular noun and oats is plural.