1) The document is a crossword puzzle containing simple past tense and past participle forms of common verbs.
2) Across clues include the simple past forms of verbs like "bring, stick, sing, eat, feed, and fly".
3) Down clues include the past participle forms of verbs like "be, take, understand, sit, go, swim, write, and stand".
4) Completing the crossword puzzle would involve filling in the blanks with the correct simple past or past participle form of the verb based on the clue.