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分钟相同 = minit sama 开始和结束的分钟一样，表示刚好经过整数个小时。方法：只比较小时，用结束的小时减去开始的小时；也可以在时间线上一小时一小时地跳，数一数跳了几次。 例子：6:40 到 10:40 → 10 − 6 = 4 小时。 注意：求时长是相减，不是把两个小时加起来。

same minutes = minit sama When the start and end have the same minutes, a whole number of hours has passed. Compare only the hours: take the start hour from the end hour, or jump one hour at a time on a time line and count the jumps. Example: 6:40 to 10:40 → 10 − 6 = 4 hours. Watch out: a duration is found by subtracting, not by adding the two hours together.

借位相减 = tukar dan tolak 把两个 24 小时制时间写成竖式，上面是结束时间，下面是开始时间。先看分钟栏：上面的分钟比下面小，就从小时借一小时换成六十分钟；再减小时栏时，记得上面的小时已经少了一。 例子：Jam 1010 − Jam 0840 → 70 − 40 = 30 分钟，9 − 8 = 1 小时 → 1 小时 30 分钟。 注意：不能因为不够减就把上下两个分钟倒过来相减。

subtract with borrowing = tukar dan tolak Write the two 24-hour times in columns, end time on top and start time below. Look at the minutes: if the top number is smaller, change 1 hour into 60 minutes; when you subtract the hours, remember the top hour is now 1 less. Example: Jam 1010 − Jam 0840 → 70 − 40 = 30 minutes, 9 − 8 = 1 hour → 1 hour 30 minutes. Watch out: do not swap the two minute numbers just because the top one is smaller.

时间线 = garis masa 用时间线分段跳：先从开始时间跳整小时，一直跳到接近结束时间、但还没超过它的时刻；再数剩下的分钟，可以先跳到整点，再跳到结束时间。最后把小时和分钟合起来。 例子：6:30 到 8:10 → 跳 1 小时到 7:30，再 30 分钟到 8:00，再 10 分钟 → 1 小时 40 分钟。 注意：答案里的分钟不会是 60 或以上，满 60 分钟要换成 1 小时。

a time line = garis masa Jump along a time line: first jump whole hours from the start until you are close to, but not past, the end time; then count the minutes left, jumping to the o'clock first and then to the end. Put the hours and minutes together. Example: 6:30 to 8:10 → 1 hour to 7:30, 30 minutes to 8:00, 10 more minutes → 1 hour 40 minutes. Watch out: the minutes in an answer are never 60 or more; 60 minutes make 1 hour.

跨中午 = melepasi tengah hari 开始在上午，结束在下午。先把下午的时间改成 24 小时制（小时加 12），上午的时间照写成四位数。然后用竖式相减：分钟不够减就借一小时换成六十分钟，小时栏少一再减。 例子：10:50 pagi 到 1:20 petang → Jam 1320 − Jam 1050 → 2 小时 30 分钟。 注意：没把下午时间加 12 就直接相减，会得到很大的错数。

crossing noon = melepasi tengah hari The start is in the morning and the end is in the afternoon. First change the afternoon time to the 24-hour system (add 12 to the hour) and write the morning time with four digits. Then subtract in columns, borrowing 1 hour = 60 minutes when needed. Example: 10:50 pagi to 1:20 petang → Jam 1320 − Jam 1050 → 2 hours 30 minutes. Watch out: subtracting without adding 12 to the afternoon time gives a far too large answer.

比较时长 = bandingkan tempoh 要找出最久的活动，先分别算出每项活动的时长：每一项都用结束时间减开始时间，跨过整点的就分两段数。三个时长都算好以后，再比较哪一个分钟数最大。 例子：甲 8:10–8:45 是 35 分钟，乙 8:45–9:15 是 30 分钟，甲比较久。 注意：不能只看哪一项结束得最晚，要比较的是时长。

compare durations = bandingkan tempoh To find the longest activity, first work out each duration: end time minus start time, counting in two parts when it crosses an o'clock. When all three are done, compare the numbers of minutes. Example: activity P 8:10–8:45 is 35 minutes and Q 8:45–9:15 is 30 minutes, so P is longer. Watch out: the activity that ends latest is not always the longest; compare the durations.