An engagement is a formal agreement between two people to be married in the future.
You can say: My friend got engaged.
My friend is engaged.
My friend is engaged to be married.
My friend recently got engaged.
My friend recently had an engagement party.
To explain the entire situation, you can say: My friend's boyfriend proposed to her recently at an engagement party. Now they are engaged to be married.
"engagement"（婚約）は、将来結婚することに対する、正式な同意をいいます。
例えば：
My friend is engaged.
（友達が婚約しました）
My friend is engaged to be married.
（友達が婚約しました）
My friend recently got engaged.
（最近友達が婚約したの）
My friend recently had an engagement party.
（友達が先日婚約パーティーを開きました）
状況全体を説明するなら、例えば：
"My friend's boyfriend proposed to her recently at an engagement party. Now they are engaged to be married."
（先日友達のボーイフレンドが婚約パーティーでプロポーズしました。今は婚約中です）
In the UK, there is no formal and binding agreement for engagement to get married. It is usually just by word of mouth between two people who state that they both wish to enter into marriage at some later date. The man would typically give the woman an engagement ring to signify his true intention. Sometimes the announcement may be made in a newspaper and be described as an 'official engagement'. This same term may also be used when the announcement is made in a more formal setting.
My girlfriend and I have a formal engagement to get married.
The couple cancelled their engagement and decided not to get married.
That is a very expensive engagement ring.
婚約 engagement
私のガールフレンドと私は結婚するために正式な婚約をしています。
My girlfriend and I have a formal engagement to get married.
夫婦は婚約を取り消し、結婚しないことを決めた。
The couple cancelled their engagement and decided not to get married.
それは非常に高価な婚約指輪です。
That is a very expensive engagement ring.
A marriage engagement is when a couple agree that they would both like to get married so are therefore taken (to be engaged means already taken)
Usually the man would give the woman a engagement ring to show his love and commitment
The definition of become is begin to be. Became is the past verb of become. Become and became are more formal versions of verbs like got. For example, you could say "My friend got engaged recently." but that is more casual language. To sound more professional, I would use the very become. "My friend has just become engaged." It sounds very professional.
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