Question

mount pinatubo is a volcanic mountain near manila, the capital of the philippines. in may 1991, scientists noticed that pinatubo was showing signs of an impending eruption. consequently, people were soon evacuated from the area. on june 12, the first major eruption occurred, spewing ash into the air. the volcano continued erupting on and off until june 15, when it exploded in the second - largest eruption of the twentieth century. the eruption was the cause of the summit collapsing into a caldera, or volcanic crater, nearly two miles across. meanwhile, tropical storm yunya was passing over the philippines. the storm brought a huge amount of rain, which mixed with the volcanic ash. as a result of the heavy ash mixture, roofs collapsed in the area.
match causes with their effects.
the volcano erupted.
roofs collapsed.
scientists saw signs of an impending eruption.
cause
effect
people were evacuated.
a caldera formed.
rain and ash mixed together.

Explanation:

• The text states that when scientists saw signs of an impending eruption, people were evacuated. So "Scientists saw signs of an impending eruption" is the cause for "People were evacuated".
• It also mentions that the eruption (the volcano erupted) led to the summit collapsing into a caldera. So "The volcano erupted" is the cause for "A caldera formed".
• And it says that rain mixed with volcanic ash (rain and ash mixed together) resulted in roofs collapsing. So "Rain and ash mixed together" is the cause for "Roofs collapsed".

Answer:

Cause: Scientists saw signs of an impending eruption. Effect: People were evacuated.
Cause: The volcano erupted. Effect: A caldera formed.
Cause: Rain and ash mixed together. Effect: Roofs collapsed.