What are the keywords in the following sentence? engagement ring in yellow gold with a purple sapphire
gold, ring, sapphire

What are the keywords in the following sentence? The piece of citrus fruit is a round orange.
fruit, orange, piece

What are the keywords in the following sentence? abstract stamp or emblem with food and cuisine written inside
emblem, stamp, write

What are the keywords in the following sentence? Two zebras looking down at the grass during grazing.
grazing, look, zebra