Eal of detailed research is being performed in this area

?I _was having___ dinner when she arrived.

?The children _were doing_____ their homework when I got home.

?While John __was sleeping____  last night, someone stole his car.

?Yesterday at this time, I ___was sitting_____ at my desk at work.

?The car engine ___stopped________ working, so I had to fix it.

?It ___was________ raining last night, so I took my umbrella.

?Ann __was having_____ a terrifying dream when the alarm clock went off at six o'clock this morning.

?Mary __was listening____ to melodious songs last evening at this time.

?While I ___was writing_______ the email, the computer suddenly went off.

?When Carol __came________last night, I __was watching________my favorite show on television.

?The plane _had taken off_____ by the time I got to the airport.