Syntax agreement simply describes adverbs that have specific meanings when used in a positive or negative sentence, and the adverb may specifically require being in a negative sentence.
Some adverbs must be used in a negative sentence. Others can be in either positive or negative sentences, but translations change. This can get quite tricky.
|全然||Extremely/a lot (Colloquial)||Not at all|
|あまり||Quite/too （あまりに Only)||Not quite/very (あまり Only)|
|[すこし・ちっと]も||Not a bit|
Point 1: Examples of the colloquial usage of 全然 include 全然大丈夫 (completely fine).
Point 2: Examples of 絶対（に） include the following.
I will never allow/forgive.
Point 3: あまり is more common in negative contexts. あんまり is a colloquial variant due to ん insertion. In positive contexts, it implies that a limit has been passed, making it similar to 非常に (very/greatly/much/quite).
I'm not really good.
4. あんまり分かんない。(Colloquial; 東京弁)
I don't quite understand.
5. あんまり運動しません。(More spoken)
I don't exercise much.
Point 4: With negative expressions とても means "simply cannot". とっても is a more forceful variant.
I simply cannot mimic.
I'm very tired.
Chinese is very difficult!
Point 5: 決して may be casually pronounced as けして.
I don't understand at all.
This door won't shut.
I don't watch television at all.
That day is a little...
Culture Note: Japanese is indirect and so are the people that speak it. When people want to decline an invitation, they often say ...はちょっと with a very reluctant tone.
まだ VS 全然 VS 全く
In a negative sentence, まだ means "yet/still hasn't." 全然 and 全く both mean "not at all," and they are both not viewed as synonyms of まだ.
It's still raining.
"Have you written it?" "No, I haven't written it yet".
Sleeping is difficult sometimes. We might tell our friends we didn't sleep at all last night even though we actually slept a little. Or, we may have a hard time falling asleep and try talking to someone in the meantime. In that situation, though, have you actually dozed off and failed to truly fall asleep, or have you been completely sleepless? With all of this in mind, we'll now learn how to express these situations in Japanese.
15a. I still haven't slept (at all).
15b. I still haven't slept any. (Have slept but not enough)
16. まだ寝ない。 VS ぜんぜん寝ない。
I still won't sleep. I won't sleep at all.
It's already morning? But I still haven't slept much at all.
18. きのうは全く寝なかった。 (You didn't sleep for even a minute)
19. きのうは全然寝なかった。 (You slept a little)
きのうは全然寝(ら)れなかった means "I couldn't sleep at all", but it sounds like you might have slept some. You might find yourself in a conversation like the following.
"Haa, I didn't sleep at all last night" "Really? You didn't sleep a bit?" "Well, I did sleep if that's what you mean, but I would wake up every thirty minutes"
Misconceptions on 全然
全然 was borrowed from Chinese about three centuries ago. At the time, it roughly equated to "completely" with both positive and negative sentences. Getting closer to modern times, its meaning narrowed to only be used in negative sentences. Now, the word has changed again in casual language to mean とても. For example, you'll hear things like ぜんぜんおいしい and ぜんぜん大丈夫. The former, though, may sometimes have the nuance of "not thinking it would be delicious but turns out it is quite alright."