rule of thumb 可不是什么奇怪的法则, 它指的是经验之谈;经验法则 通常会和 general / good 搭配使用 举个例子: As a general rule of thumb, children this age should not spend more than one hour on homework. 照理说,这个年龄的儿童家庭作业不应超过一个小时。 cut to the chase 指的是不绕圈子直截了当地说,开门见山 比如说: Right, let's cut to the chase. How much is it going to cost? 对啦,咱们开门见山吧。这要多少钱? sack 有麻袋的意思,the sack 可以指床,所以 hit the sack 意思就是上床睡觉了。 另外 hit the hay 也可以指上床睡觉 比如说: It's one o'clock – time to hit the sack. 一点钟了 — 该睡觉了。No.1 rule of thumb 经验之谈;经验法则
No.2 cut to the chase 开门见山
No.3 hit the sack 上床睡觉