5. Rocks: Adding circumstances

Your task is to add a circumstance to each short clause.

A circumstance is a group of words (often a prepositional phrase) that tells us

where, when, or how the process happens.

Write a prepositional phrase for the type of circumstance shown in brackets for each clause.

5.1. Example

Clause: Basalt cools (place)

With circumstance: Basalt cools on the surface after an eruption.

Adding circumstances

Rewrite each short clause by adding a circumstance.

process + circumstance

Simple clause (noun + verb)	With added circumstance
Basalt cools.	Basalt cools (place) __________________ on the surface after lava erupts.
Granite hardens.	Granite hardens (place) _______________ deep underground over millions of years.
Obsidian breaks.	Obsidian breaks (manner) _______________ with a sharp, glassy fracture.
Pumice floats.	Pumice floats (manner) _________________ because of trapped gas bubbles.
Sandstone crumbles.	Sandstone crumbles (place) ________________ along exposed cliff faces.
Marble reacts.	Marble reacts (manner) _______________ when exposed to weak acids.
Limestone dissolves.	Limestone dissolves (manner) _______________ in slightly acidic groundwater.

Reveal Answer Key

Model Answers

Process + Circumstance

Simple clause	With added circumstance
Basalt cools.	Basalt cools on the surface after lava erupts.
Granite hardens.	Granite hardens deep underground over millions of years.
Obsidian breaks.	Obsidian breaks with a sharp, glassy fracture.
Pumice floats.	Pumice floats because of trapped gas bubbles.
Sandstone crumbles.	Sandstone crumbles along exposed cliff faces.
Marble reacts.	Marble reacts when exposed to weak acids.
Limestone dissolves.	Limestone dissolves in slightly acidic groundwater.