一般式： 用doing,being done 各造4个句子. 完成时： 用having done,having been

Seeing his mother,the boy jumped in joy.
Hearing the news,she cried.
Walking along the stream, I met a group of hikers.
Not knowing what to do,she came to ask for my advice.

Being questioned by the police, the boy got very nervous.
Being left on her own,the little girl didn't know what to do.
Being made in China, these toys are of good quality.
Being caught in the traffic, Tom grew impatient.

I'm doing my homework.
He is doing the housework.
The artwork is now being done by Jimmy.
The translation is being done by Rose at this moment.