自2010年至今的四级考试中， 共出现过 次
自2010年至今的六级考试中， 共出现过 次
VERB 探索；探究 If you plumb something mysterious or difficult to understand, you succeed in understanding it.
She never abandoned her attempts to plumb my innermost emotions...
Magda had plumbed her own heart for answers.
ADV 恰恰；正好 If something is plumb in a particular place, it is exactly in that place.
The hotel is set plumb in the middle of the high street...
Grenville took another wallop plumb on the jaw.
VERB 为（建筑物）敷设水管 When someone plumbs a building, they put in all the pipes for carrying water.
She learned to wire and plumb the house herself.
ADV 完全地；不折不扣地 Plumb is used to give emphasis to an adjective or verb that describes a feeling or condition.
I find I'm plumb depressed by it...
This thing has plumb worn me out.
PHRASE 经受极度的…；表现出极端的… If someone plumbs the depths of an unpleasant emotion or quality, they experience it or show it to an extreme degree.
They frequently plumb the depths of loneliness, humiliation and despair...
Is this the first of many questions that will plumb the depths of stupidity?
PHRASE 糟糕到新低点；降至最低点 If you say that something plumbs new depths, you mean that it is worse than all the things of its kind that have existed before, even though some of them have been very bad.
Relations between the two countries have plumbed new depths...
Last night's harrowing television pictures plumbed new depths of depravity.