span

n.

[C] a period of time between two dates or events （两个日期或事件之间的）时距，期间Property gained within the span of marriage such as salary is considered jointly owned property. 婚姻存续期间获得的财产，如工资，都视为夫妻共同财产。

The average life span for Americans is now more than 74 years. 美国人的平均寿命现在超过了74年。

scratch

n. [C]

1 (from ~) from a point where nothing has been there, so you have to do everything yourself 从零开始；从头开始；白手起家

It may be the first time in years when you have had to start from scratch making new friends. 这可能是多年来的第一次你不得不从头开始结交新朋友。

2 a thin mark or cut on the surface o f sth. or on sb.‘s skin （物件或皮肤上的）刮痕，划痕The scratch on the watch was almost too minute to see. 手表上的划痕几乎小得看不见。tune

vt.

1 (also ~ up) make small changes to an engine so that it works as well as possible 调整，调节（发动机）使达到最佳状态

In order to keep drivers safe, mechanics are urged to make sure that car engines are properly tuned up. 为了保证司机的安全，一定要敦促机械师确保汽车发动机已调整好。

2 make small changes to a musical instrument so that it will produce the correct notes 为（乐器）调音，定弦

Someone is coming tomorrow to tune the piano. 明天会有人来给钢琴调音。

adjust

v.

change or move sth. slightly to improve it or make it more suitable for a particular purpose 调整；调节

The figures have been adjusted for inflation. 数据因通货膨胀而作了调整。

vi.