be careful when you are crossing the street.可以改写成be careful when crossing the street.when my mother saw that i was unhappy,mother called me to her bedroom.可以改写成seeing that i was unhappy ,mother called me to he bedroom.为什么第一句有when而第二句不用when?

问题描述:

be careful when you are crossing the street.可以改写成be careful when crossing the street.
when my mother saw that i was unhappy,mother called me to her bedroom.可以改写成seeing that i was unhappy ,mother called me to he bedroom.为什么第一句有when而第二句不用when?

seeing that 是由于的意思 , 表示原因

  be careful when you are crossing the street,说话的对象应该是你,你们,所以可改写成be careful when crossing the street.
  seeing that i was unhappy ,与后面的mother called me to her bedroom,这两个动作应该是同时发生的,seeing that i was unhappy 这里可理解为伴随状语.句子意思为:母亲见我不开心就把我叫到她的卧室去.