The three sentences you see provided above are terrific ways to express to your listener that you are not always kind. In the third sentence you will notice the noun case. Although this word has different meanings in this sentence it means situation or circumstance. This is a word that can be used in both formal and informal settings and it would make a great addition to your vocabulary.
You can simply respond with, "Not always".
But if you want to be more specific, you could say, "I am not always kind to you". or "That is not always the case".
Also, the phrase "not all the time" is very common. This shows a contrast to the statement made by the other person.
シンプルに「Not always」と答えることができます。
より具体的に言いたいなら、例えば：
"I am not always kind to you".
（いつも優しくはないよ）
"That is not always the case".
（いつもそうというわけではないです）
他に「not all the time」というフレーズもよく使われます。これは相手の言ったこととの違いを表します。
Most of the time would mean you're most of the time kind with a few exceptions. It's a much better way of saying than "not always". Not always gives out kind of aggressive vibes.
Sometimes can also be used and would also mean you're in some situations kind while others not.
Hope this helps!
「most of the time」は、（そうでないこともあるけど）ほとんどの場合は親切という意味になります。これは「not always」よりもずっといい言い方です。「not always」は少し攻撃的な感じになります。
「sometimes」も使えます。これは、親切な時もあるという意味になります。
参考になればと思います。
"I can be, but not always" is a great way to say you aren't disagreeing with what they are saying or arguing, but that it isn't the full truth. By saying "I can be.." you are acknowledging their opinion and not just saying it's not true. EG: "You are such a healthy eater!" "I can be, but not always. On the weekends I like to eat junk food".
"Yes, but not all the time" is also a great way to acknowledge what the person is saying and add that sometimes it is another way. EG; "You are so nice to your sister." "Yes, but not all the time. Sometimes she really annoys me."
"I try to be, but sometimes I'm not" is a response you can give when someone says you are something that you are aiming to be. For example, a complement that you can agree you try to be that way, but you also are acknowledging that you don't always succeed. EG: "You are so kind" "I try to be, but sometimes I'm not when I'm in a bad mood or I've had a bad day".
"I can be, but not always."
（いつもってわけではないよ）
- 相手の言っていることが間違いではないが完全に事実ではない場合に使います。「I can be..」と言って、相手の意見を認めています。
例：
"You are such a healthy eater!" "I can be, but not always. On the weekends I like to eat junk food".
〔訳〕「健康に気を遣ってるね」「いつもってわけではないよ。週末はジャンクフードとかよく食べるし」
"I try to be, but sometimes I'm not."
（そうなるように努力はしているけど、いつもってわけではないよ）
- 自分がそうなろうと努力していることについて言われた時に使います。例えば、自分がそうなろうと努力していることについて褒められた時に、いつもうまくいくわけではないと伝えられます。
例：
"You are so kind." "I try to be, but sometimes I'm not when I'm in a bad mood or I've had a bad day."
〔訳〕「すごく優しいね」「努力はしているけど、そうでないこともあるよ。機嫌が悪い時とかうまくいかない日は」
Although I may not always be as kind as you imagine
Yes, I try, but there may be moments when I'm not so kind also
I would hope so. But I may not always be the person you think I am
When someone says something like "You are always so kind" to me, you want to say that it's "not always". Above are a couple of suggested responses which may be suitable for that kind of conversation.
ある人が、 "You are always so kind"（いつも親切ですね。）と言ってくれて、 "not always"（いつもではないよ。）ということができます。これらの例は、このような場面で使うことのできるフレーズです。
Ex...I sometimes go to the theme park.
Ex..I go out for drinks occasionally.
Sometimes and occasionally are adverbs of frequency which tell us how often something is done.. We use them to talk about actions that are least frequent.
例：I sometimes go to the theme park.
（時々テーマパークに行きます。）
例：I go out for drinks occasionally.
（たまに飲みに行きます。）
Sometimesやoccasionallyは、時々という意味の副詞です。頻繁にしないことに対して使う言葉です。
All of the above are phrases we can use to describe how often we do something.
'Occasionally' is an adverb of frequency. Adverbs of frequency are used to describe how often we do something. To do something 'occasionally' or 'on occasion' means to do something sometimes, but not frequently.
上記のフレーズは全て、頻度を表すときに使います。
'occasionally' は 'adverb of frequency'（頻度を表す副詞）です。'adverb of frequency' は頻度を表すときに使われます。
'occasionally' または 'on occasion' は「（「頻繁」でなく）時々」という意味です。
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