1.electric cars 电动汽车

例句:Hybrids, unlike pure electric cars, never need to be plugged in.
与纯电动汽车不同，混合动力车永远不需要接电源。

2.set aside 留出；撤销

例句:Some doctors advise setting aside a certain hour each day for worry.
一些医生建议每天抽出一定时间思忧。

3.dropped out of 退出；辍学

例句:He'd dropped out of high school at the age of 16.
他16岁的时候就从中学退学了。

4.single-mindedness 专心

例句:Their dogged single-mindedness is almost heroic.
他们不屈不挠专心致志的劲头简直是一种壮举。