To say that you are finishing school, you are finally graduating - you can say "I will be graduating this summer", this doesn't necessarily imply you will be attending the ceremony so to make it more clear you can say the second phrase. However, this is more formal.
An informal phrase wold be "I'm going to my graduation on Tuesday".
学校が終了するという事は、とうとう卒業するという事ですね。
次のように表現することが出来ます。
"I will be graduating this summer"
（この夏卒業します）
卒業式に出席することをほのめかす必要はありません。
ですので、はっきりさせるために二つ目のフレーズで言い表すことが出来ます。
ですが、これは少しフォーマルです。
カジュアルな表現は
"I'm going to my graduation on Tuesday".
（火曜日に私の卒業式に行きます）
graduate = 卒業する
graduation = 卒業式
graduate from high school = 高校を卒業する
"Friday is my valedictory"
"We will be having a commencement at school"
"I am so excited for Graduation Day"
"Valedictory" expressing or containing a farewell and can describe high school graduation. It is the address or statement of farewell. "Graduation day" the day you complete your high school career and go for tertiary education. "Graduation " is the acceptance of an academic degree or diploma. "Commencement" is the ceremony in which degrees or diplomas are conferred on graduating students.
例文
"Friday is my valedictory"
（金曜日は私の卒業式だ）
"We will be having a commencement at school"
（学校で卒業式がある）
"I am so excited for Graduation Day"
（卒業式が本当に待ち遠しい）
"Valedictory"には「告別演説」「別れの言葉」という意味があり、高校の卒業式を表すことがあります。
"Graduation day"は、高校生活を終え、大学へと進む日です。
"Graduation"は、学位や卒業証書を受け取ることです。
"Commencement"は、卒業生に学位や卒業証書が授与される儀式のことです。
I will participate in my high school graduation ceremony.
After many years of hard work studying in high school, you will graduate and participate in the high school graduation ceremony.
You will be given a diploma for completing high school and there may be students and teachers who give a motivational speech.
The ceremony for graduating high school is called 'high school graduation ceremony' or, 'graduation ceremony'.
"I will participate in my high school graduation ceremony."
to 'participate' in = this means to take part in, to have a role in something.
"I will be in my high school graduation ceremony."
to 'be in' something = this means to attend something and have a reason or purpose for doing it.
Likewise, you can say that you will 'attend' the high school graduation ceremony, but this very 'attend' means to come and watch it happen.
高校で何年もたくさん勉強した後に卒業する際は卒業式に出席するでしょう。
高校を修了すると卒業証書が与えられ、生徒や先生による激励のスピーチが行われることがあります。
高校の卒業を祝う式は、'high school graduation ceremony'や'graduation ceremony'と呼ばれます。
【例文】
"I will participate in my high school graduation ceremony."（高校の卒業式に出席します）
to 'participate' inとは、to take part in（参加する）、to have a role in something（役目を果たす）という意味です。
"I will be in my high school graduation ceremony."（高校の卒業式に出ます）
to 'be in' somethingとは、何か理由や目的があって何かに出席することです。
同様に、you will 'attend' the high school graduation ceremony（高校の卒業式に出席する）と言うこともでき、この'attend'は訪れて起こることを見るという意味です。
The graduation ceremony of high school is called "High School Graduation"
In South Africa, we call it "Final assembly" or "Valedictory"
"I will be part of the graduation this year" explains that you will be doing something at the ceremony.
"I will be graduating this year" This explains that you will be passing high school this year.
高校の卒業式の事を "High School Graduation"と呼びます。
南アフリカでは"Final assembly" や"Valedictory"と呼ばれます。
"I will be part of the graduation this year"
（今年は卒業式に参加します）
これはその式典で何かをする事を説明しています。
"I will be graduating this year"
（私は今年卒業します）
これは今年高校を卒業するという事を説明しています。
If you completed the studies successfully, then it is normal to have a graduation ceremony. It is not necessary to say you will be participating in it as that is the natural assumption when you talk about "My high school graduation." However in the case of being unable to attend, then that would need to be stated as that is a departure from the norm.
"I shan't be attending my high school graduation,"
「My high school graduation（私の高校卒業式）」と言えば、参加することは分かりますからわざわざ「participate（参加する）」と言う必要はありません。ただ、参加できない場合は、それをはっきり言わないといけません。普通のことではないので。
例：
I shan't be attending my high school graduation.
私は、高校の卒業式には出席しません。
こんにちは。
「高校の卒業式」は英語で high school graduation (ceremony) と言えます。
high school が「高校」、graduation が「卒業」、ceremony が「式」ですが、ceremony は略されることも多いです。
【例】
My high school graduation is tomorrow.
「明日は高校の卒業式です」
When is your graduation ceremony?
「卒業式はいつ？」
ぜひ参考にしてください。
I will be taking part in my high school graduation ceremony.
I will be participating in my high school graduation ceremony.
I will be graduating this year.
The word "ceremony" means that it is a special occasion taking place. If you are graduation high school, we usually put the words together and call it a "high school graduation ceremony".
If you will be part of it, you could use any one of the above mentioned examples:
1."I will be taking part in my high school graduation ceremony"- "taking part" means to participate.
2."I will be participating in my high school graduation ceremony"- This means the same as the first one.
3."I will be graduating this year"- The word "graduating" encapsulates that you are going to be at the high school ceremony and you will receive your diploma.
Thank you for your question, hope this helps!
ご質問ありがとうございます。
・「high school graduation ceremony」
＝高校の卒業式
（例文）My high school graduation ceremony is next month.
（訳）私の高校の卒業式は来月です。
（例文）When is your high school graduation ceremony?
（訳）高校の卒業式はいつですか？
お役に立てれば嬉しいです。
Coco
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