1. arrived - was still sleeping

2. went- were having

3. was having- stopped

4. were crossing- saw

5. saw- was standing

6. was reading- was learning- was doing

7. were playing- came

8. rang- was taking

9. was- worked

10. was sitting- saw

when i was arriving at this house,he was still sleepping

the light was going out while we were having dinner

bill had breakfast when i stopped at this house this morning

as we were crossing the street,we were seeing an accident

tom was seeing a serious accident while he was standing at the bus stop

while my father was reading a newspaper,i was learning and my sister was doing her homework 

the children were  playing football when their mother was coming back home

the bell was ringing while tom was taking a bath

i was very tired because i worked all day yesterday

he was sitting in a cafe when i was seeing him

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