The have a picnic / it start to rain
They were having a picnic when it started to rain. / While they were having a picnic, it started to rain.
watch TV / go out
While they were watching TV the heating went out./ They were watching TV when the heating went out.
We rehearse / lights go off
While they were rehearsing, the lights went off. / They were rehearsing when the lights went off.
She read / phone ring
She was reading a book when the phone rang. / While she was reading a book, the phone rang
They skate / he fall down
They were skating when he fell down. / He fell down while they were skating
She talk on phone / the man take it
She was talking on the phone, when the man took it./ While she was talking on the phone, the man took it.
He peel / he cut
He was peeling the carrot when he cut his finger. / He cut his finger while he was peeling the carrot.
I cook / explode
She was cooking *baking( when the cooker exploded / The cooker exploded while she was cooking.