If the wound or cut is not getting better quickly, then you can say that it is "slowly healing" or to emphasize the slowness, put "slowly" at the beginning of the sentence, "Slowly, my wound is healing".
Another way to say "gradually" is, "it is taking time". For example, "The cut, it is getter better but it is taking time". Again, to add emphasis you can say "some time".
傷や、切り傷が早く良くならない場合、slowly healingと言えるでしょう。又は、文の最初にslowlyを入れて遅さを強調します。
例：
Slowly, my wound is healing.
ゆっくりと、傷が治ってます。
他の言い方では、graduallyで、時間がかかってるという意味です。
例えば、The cut, it is getter better but it is taking time.（切り傷は良くなってますが、時間が掛かってます。）
この場合も先と同様に、some timeを加えると強調できます。
▪ My wound is healing nicely.
This is saying that your cut/sore is in the process of becoming better.
A sore is a place on your body that is painful like a cut or wound.
▪ Slowly but surely my wound is getting better.
This sentences is indicating that it is taking longer than expected for the wound to get better but it is getting better.
▪ My wound is healing nicely.
（傷が順調に回復しています。）
自分の切り傷や腫れなどの痛むところが回復の過程にあると伝えています。
A sore とは体の痛んでいる部分のことで cut （切傷）や wound（怪我）も含みます。
▪ Slowly but surely my wound is getting better.
（ゆっくりと、でも確かに私の傷はよくなっています。）
こちらの表現は傷の回復が期待していたより長くかかっているけれど、良くなってきてはいると示唆しています。
"The wound is healing nicely." You could say this if someone asks how you are. You are telling them that the wound is healing without any problems, like infection etc.
"I am on the mend." (Mend - to get better or heal.) You can use this if you are talking about a bad cut, a broken limb or if you have had a surgery. You are on the mend, you are getting better!
例文：
"The wound is healing nicely."
(傷が段々と良くなってきています。）
もし誰かが調子を尋ねてきたらこのように答えることができます。この表現では相手にあなたの傷は感染などの問題もなく順調に回復していると伝えています。
例文：
"I am on the mend."
（回復中です。）
(Mend -良くなるまたは回復する )
酷い切傷や肋骨の骨折などについて話しているときや、手術を受けた後などにはこちらの表現も使えます。You are on the mend. とは、あなたの体調が良くなってきているという意味です。
*The wound is gradually healing / I'm recovering well from the leg injury. -Both words healing and recovering shows that a person is getting better from an injury, cut, wound or any other health condition.
The wound is gradually healing.
傷が徐々に治ってきている。
I'm recovering well from the leg injury.
足の怪我から回復してきている。
healing、recoveringという言葉どちらも、怪我、切り傷、その他の状態からよくなってきているという意味です。
"Its getting better." Means that the injury is healing
"It's healing." This means the injury or cut is getting better.
"It's getting better with time." This explains that the injury/cut/sore is getting better and better with the more time that passes.
I / he/ she, etc is getting better now. / is recovering now.
If a wound or injury is healing, it is recovering back to normal.
"On the mend" is an informal expression meaning the same thing.
Example: I am glad to hear that your injury is getting better now and you should soon be well.
His wound is healing and he will soon be fit.
saying my injury is gradually getting better is a good way of explaining this. the word 'gradually' means slowly.
saying "my wound is healing slowly" is also a good way of describing this. saying 'healing slowly' means that your injury is gradually improving.
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