a head of lettuce

基本解释

We need a head of lettuce, a bunch of carrots, and a bag of onions.
我们要一棵生菜，一把胡萝卜和一袋洋葱。
dict.cn
It's productive. You can get a head of lettuce from seed to your plate in six weeks — from a tank in your backyard.
在6周的时间内，一颗水灵灵的莴笋就从种子变成了你的盘中佳肴---这可是你家后院的鱼缸里出产的！
Washed and bagged greens can be a time-saver, but they can cost three times as much as buying the same amount of a head of lettuce.
购买洗净、包装好的绿色蔬菜可能会节省时间，但这可能比购买等量的一棵莴苣要贵三倍。

Like a head of lettuce, a leveraged investment partnership wilts easily.
FORBES: Clipped Hedges
Like a head of lettuce, a leveraged investment partnership easily wilts.
FORBES: Clipped Hedges
You know how hard it is for your parents if they have to get on a bus to go get a head of lettuce and they just came home from work and they have to get in a cab to go to a grocery store -- that's hard and expensive for them, right?
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