例句：

　　He described the difficulties of surviving for four months as a captive.

　　他描述了被俘4個(gè)月里掙扎求生的艱難歲月。

　　The election was held six months ahead of schedule.

　　選舉提前了6個(gè)月舉行。

　　The area has been the scene of fierce fighting for three months.

　　這一地區(qū)3個(gè)月以來(lái)不斷發(fā)生激戰(zhàn)。