The towns are connected by train and bus services.

He arrived in Shenyang by train yesterday.

他昨天乘火车到达沈阳。

Couldn'tthey send it by train?

他们不能用火车运过来吗？

Granny travelled down by train.

奶奶是乘火车过来的。

We've stopped transporting weapons to this country by train.

我们已停止用火车向该国运送武器.

Specific behaviour must be determined by trial and error.

特殊的行为必须是通过探索试验来决定.

They didn't know how to put in a central heating system, but they managed it by trial and error.

他们不知道怎样安装集中供暖设备, 但是经过反复试验终于安装好了.

Many drugs were found by trial and error.

很多药物都是通过反复试验才发现的。

She looked at Jane, smiled shook by turns.

她一会儿望望吉英, 一会儿笑笑,一会儿摇摇头.

The two workers carried the load by turns.

这两个工人轮流超负荷工作.

When Mary had a fever, she felt cold and hot by turns.

玛丽发烧时, 她感到忽冷忽热.

When John had a fever, he felt cold and hot by turns.

约翰发烧时感到冷一阵,热一阵.

The two sisters took care of their sick mother by turns.

两姐妹轮流侍候生病的母亲.

You two will stay with the sick person by turns.

你们二人轮流地看守这位病人.

When George had a fever, he felt cold and hot by turns.

当乔治发烧的时候, 他感到一阵发冷一阵发热.

The old Roman armies had several generals who took command by turns.

古罗马的军队由几位大将轮流指挥.

Those of my own life , who by turns had flung.

我自己的年华, 把一片片黑影接连着.

Walling and resting by turns , he wandered about until noon without the energy to solicit fares.

走一会儿,坐一会儿, 他始终懒得张罗买卖.

Mary and Jane rode by turns.

玛丽与珍尼轮流骑马.

He gets cheerful and depressed by turns.

他的情绪高一阵低一阵.

We did the work by turns.

我们轮流干这活.