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i couldn't answer the question because...
she was hungry because...
my mother worried because...
they were late because...
the boy was pleased because...
he arrived at John's the house because...

I couldn't answer the question because i hadn't read this theme she was hungry because she hadn't eaten my mother worried because i hadn't answered her telephone call.They were late because they had missed the bus. The boy was pleased because he had won tennis tournament He arrived at John's house because he had had problems to decide with John.