手机是其中一项最伟大的发明，人们可以随时随地地保持联系。

Cell phone is one of the biggest inventions, people can keep in touch with each other anytime and anywhere.

youdao

手机是其中一项最伟大的发明，人们可以随时随地地保持联系。

Cell phone is one of the biggest inventions, people can keep in touch with each other anytime and anywhere.

youdao