adj.無背的；無靠背的

Rose bushes shoot again after being cut back. 玫瑰叢修剪後還能再長出新枝。

He trudge three hour in the snow to get back home. 他在雪中跋涉三個鐘點才回到家。

Do exercise every day and you'll be back in condition. 每天鍛煉鍛煉，你很快會恢復(fù)健康的。

The ship beat back against a monsoon. 船逆著季風艱難地行駛。

I flap the flies away but soon they fly back. 我把蒼蠅趕走，但一會兒又飛回來了。