那男孩子正在帮助一个老人过街用英语怎么说

Look! That boy is helping an old man ( to)cross the street.
help sb. do sth.= help sb. to do sth.

Look! That boy is helping an old man walking across the street.

Look!That boy is helping an old man to cross the street.

Look! The boy is help a man across the street