I usually edit on the Simple English Wikipedia. Have started here in December 2008.
Things to help me: change
Countable: If the definition can't start with "a" or "an" (e.g., An insurance is...), then it's most likely not countable.
Transitive: if you can put a noun after it for a given meaning in a simple sentence (e.g., I used the computer), it's transitive
Intransitive: if you can use it without a noun following, it's intransitive (e.g., I slept). If you can alternate without changing the meaning (e.g., I ate (a sandwich) earlier), then it's both.