5 halve

halve
v[Tn]
1 divide (sth) into two equal parts 把(某物)对半分
    halve an apple 把一个苹果分成两半.
2 reduce (sth) by a half 把(某物)减半
    The latest planes have halved the time needed for crossing the Atlantic. 最新型号的飞机把飞越大西洋所需的时间减少了一半.