Tra từ hardly - Từ điển American Heritage Dictionary 4th

hard·ly (härdʹlē)adv.
1. Barely; just.
2. To almost no degree; almost not:
I could hardly hear the speaker.
3. Probably or almost surely not: “Easily was a man made an infidel, but hardly might he be converted to another faith” (T.E. Lawrence).
4. With severity; harshly.
5. With great difficulty; painfully. [Middle English hardli, from Old English heardlīce, harshly, bravely, from heard, hard. See hard.]
Usage Note: In Standard English, hardly, scarcely, and similar adverbs cannot be used with a negative. The sentence I couldn't hardly see him, for instance, is not acceptable. This violation of the double negative rule is curious because these adverbs are not truly negative in meaning. The sentence Mary hardly laughed means that Mary did laugh a little, not that she kept from laughing altogether, and therefore does not express a negative proposition. But adverbs like hardly and scarcely do share some important features of negative adverbs, even though they may not have purely negative meaning. For one thing, they combine with any and at all, which are characteristically associated with negative contexts. Thus we say I hardly saw him at all or I never saw him at all but not I occasionally saw him at all. Similiarly, we say I hardly had any time or I didn't have any time but not I had any time and so on. Like other negative adverbs, hardly triggers inversion of the subject and auxiliary verb when it begins a sentence. Thus we say Hardly had I arrived when she left on the pattern of Never have I read such a book or At no time has he condemned the movement. Other adverbs do not cause this kind of inversion. We would not say Occasionally has he addressed this question or To a slight degree have they changed their position. The fact is that adverbs such as hardly can be said to have a negative meaning in that they minimize the state or event they describe. Thus hardly means “almost not at all” rarely means “practically never” and so forth. This is why they cannot be used with another negative such as not or none. See Usage Note at double negative. See Usage Note at rarely. See Usage Note at scarcely.