Дополните предложения глаголом в past simple, past continuous или past perfect. preform a)dr.stephens an experiment while his students were watching him. b) dr. stephens lot of experiments before he made an important discovery. c)two weeks ago dr. stephens an experiment with the help of some university students. fall a) the baby asleep, as soon as we put her bad. b) as the baby asleep, she was making some funny sounds. c) the baby asleep by the time he got home and he didn't want to wake her up. read a) laura the report many times before she gave it to her boss. b) while laura the report, her computer started making strange noises and stopped working. c) laura the report, switched off her computer and went home.

Preform 

A)Dr.Stephens was performing an experiment while his students were watching him.
B) Dr. Stephens had performed a lot of experiments before he made an important discovery.
C)Two weeks ago Dr. Stephens performed an experiment with the help of some university students.

fall

A) The baby fell asleep, as soon as we put her bad.
B) As the baby was falling asleep, she was making some funny sounds.
C) The baby had fallen asleep by the time he got home and he didn't want to wake her up.

read

A) Laura had read the report many times before she gave it to her boss.
B) While Laura was reading the report, her computer started making strange noises and stopped working.
C) Laura read the report, switched off her computer and went home.