If you can't get a cab, give me a call. It's not safe to walk home along at night.
如果你叫不到出租车的话,打电话给我,晚上一人走回家不安全。
Instruments have been devised and can be so placed that all three elements can be recorded in different graphs.
已经设计出了一些仪器,它按照一定的安放方式就可测绘出这三种运动的曲线图。