Double quotes are ", single quotes are ', parentheses are b or (, square brackets are [, curved brackets are {. Use "a" includes quotes and brackets, otherwise "i". So:
da": delete words with double quotes;
ya": copy words with quotes;
ca": delete and insert words with quotes;
dab: delete words with parentheses;
da[: delete words with square brackets;
da{: delete words with curved brackets;
yi": copy words inside the double quotes;
yi': copy words inside the single quotes;