例句：

　　That purpose is alertness.

　　這個目的就是警惕。

　　They also increase alertness and energy.

　　它們也能提高機(jī)敏性和精力。

　　Alertness must be bred into every soldier.

　　警惕性必須滲透到每個戰(zhàn)士的血管中去。

　　We look forward to greater mental alertness.

　　我們渴望突破精神上的限制。

　　And the body is made sensitive through alertness.

　　而身體因警覺而變得敏感。