What are the keywords in the following sentence? a student is typing on her laptop .
laptop, student, type

What are the keywords in the following sentence? a fallen tree blocking the road .
block, road, tree

What are the keywords in the following sentence? detail of annual rings of a tree trunk in the forest .
detail, forest, trunk

What are the keywords in the following sentence? still partially raised after allowing a boat to pass
boat, pass, raise