Sentence Structuring

[cleung]

I remember having read some sentences like the ones below, and I'd appreciate it if someone can please tell me what kind of sentence structure this is called. I'm baffled by the opposite meanings of the adj. and adv. used within the sentence. Thanks for your help.

1. Davis operates as covertly as Walsh does overtly.
2. The husband is as conservative as the wife is aggressive.

[fromatto]

I remember having read some sentences like the ones below, and I'd appreciate it if someone can please tell me what kind of sentence structure this is called. I'm baffled by the opposite meanings of the adj. and adv. used within the sentence. Thanks for your help.

1. Davis operates as covertly as Walsh does overtly.
2. The husband is as conservative as the wife is aggressive.

It's simply 'as + adjective/adverb + as.....', for comparison. Since there are two people involved in both cases, it is a moot point whether these are 'opposites meanings'. Covert IS the opposite of overt, but conservative and aggressive ? Davis's actions are as covert as Walsh's are overt. I 'believe' the technical term for this is 'adverbial clause of comparison'.