What are the keywords in the following sentence? The train is coming in to the section of track near the switches.
come, switch, track, train

What are the keywords in the following sentence? small streams as the rain falls in the tropical forest
forest, rain, stream

What are the keywords in the following sentence? politician greets fans and signs copies of his book
book, copy, fan, sign

What are the keywords in the following sentence? both lanes were blocked until the wreckage was cleared .
block, clear, lane