Each sentence takes a place in a specific moment, and aspects tell us the status of the action at that moment
Past
Continuous/Progressive
“We were sleeping when the sea creature attacked.”
Perfect
“We had departed from Nantucket.”
Perfect Progressive
“We had been sailing three weeks.”
Simple
“We went to search a sea creature.” “Sea creature attacked us.”
Present
Continuous/Progressive
“We’re preparing for their next mission.”
Perfect
“We have built a special submarine for the search mission.”
Perfect Progressive
“We have been researching possible sightings of the creature.”
Simple
“We still search for the sea creature today.”
Future
Continuous/Progressive
“Our friends will be searching for the elusive creature.”
Perfect
“The submarine will have reached uncharted depths a month from now.”
Perfect Progressive
“We will have been voyaging for three weeks.”
Simple
“We will depart next week.”
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