Four years have elapsed since he went to London.

自从他伦敦, 已过四年。

Five months have elapsed since he joined the army.

"自从他参军以后,已经五个月。"

A month elapsed, the girl was narcose all the same.The boy was peaked and pined, but he still believed that she would get better one day.

一个月过，仍然昏睡着，而男早已憔悴不堪，但他仍苦苦地支撑着。