こんにちは。
「参加者」は participant と言います。
[パーティー](https://eikaiwa.dmm.com/uknow/questions/63145/)のような場合は guest という言葉も良いかもしれません。こちらは日本語の「[ゲスト](https://eikaiwa.dmm.com/uknow/questions/56178/)」と同じようなニュアンスです。
【例】
Participants can enjoy free food and drinks.
「参加者は[無料](https://eikaiwa.dmm.com/uknow/questions/38664/)で食事と飲み物をお楽しみいただけます」
How many guests will be coming to the party?
「パーティーには何人のゲストが来ますか？」
ぜひ参考にしてください。
The three sentences you see above are terrific ways to express to your listener that you are participating in a meeting or party. The first two sentences are appropriate for a formal setting, like a business meeting or a presentation. The third sentence is appropriate for an informal setting, like when we are talking with close friends or family.
As may be seen from the above suggestions, it depends to some degree on the type of group we are talking about.
"The party-goers seemed to be enjoying themselves."
どのようなグループの集まりなのかにも寄るので、いくつか該当する用語をご紹介します。
例：The party-goer seemed to be enjoying themselves.（パーティーの参加者は楽しんでいるようだ。）
"Player" or "Competitor" is used for someone who participates in a contest or game. Where as a "participator" is a person who participates in something like an event, seminar, conference, etc.
All the words mean the same thing but it depends on what event to how you would use them for example
1) a participant would be someone would is participating in a meeting
2) An atendee or guest could be used when someone is having a party as an attendee is someone attending the party and guest is used when someone has been invited to the party
An 'associate' is a business term used to describe someone that you do business with, and may be attending a meeting with you.
A 'guest' is someone that you have invited or has been invited to a party, meeting or any kind of event.
When some is a 'partaker' it means that they are taking part in something. Again, this cold be any kind of event, special occasion or gathering of friends.
参加者は英語で participantと言います。複数形は participants です。
例）
パーティーの参加者は何人？
How many participants will there be for the party?
彼はミーティングの参加者の一人だった
He was one of the participants at the meeting
ご参考になれば幸いです。
「参加者」はイベントに種類によって英語の言い方が違います。例えば、パーティーの場合、「guest」という言い方を使います。コンテストやコンクールのようなイベントの場合、「participant」、「competitor」などの言い方を使います。ミーティング、セミナーの場合、「attendee」という言い方を使います。
There were many guests at the party.
（パーティーには数多くの客が来ました。）
Here is a list of participants.
（これは参加者のリストです。）
How many attendees will there be?
（参加者は何人がいますか？）
Term you can use to refer to a person who takes part in something, you can use the terms "participant" or "participator".
For example, you may say:
-I was a participant in last year's marathon.
参加者のことは"participant"や"participator"と言えます。
例えば、次のように言うことが出来ます：
-I was a participant in last year's marathon.
［訳］私は去年のマラソン大会の参加者でした
日本語の「参加者」が英語で「participant」といいます。
以下は例文です。
パーティーの参加者 ー Party participant
ミーティングの参加者 ー Meeting participant
参加者は何人いますか ー How many participants do we have？
ミーティングの参加者が４人です ー There are 4 participants in this meeting
参考になれば嬉しいです。
He was a participant in the last championship game.
Japan will have lots of participants in the next Olympics.
I wanted to be a participant, but my abilities weren't good enough to make the team.
参加者 participant
彼は最後の優勝ゲームの参加者でした。
He was a participant in the last championship game.
日本には、次のオリンピックに多くの参加者がいるでしょう。
Japan will have lots of participants in the next Olympics.
私は参加者になりたかったのですが、
私の能力はチームを作るのに十分ではありませんでした。
I wanted to be a participant, but my abilities
weren't good enough to make the team.
The usual word is "participant". Synonyms include "member", "partner"
"competitor" and "player"
A participant is someone who takes part in something such as a competition, meeting, survey, project, game, etc. It is a general word to describe someone who takes part in such things, while the other words have more specific applications. For example, you could say that someone is a member of an organization, someone is a partner in a business, competitor in a sport and player of a game.
if somebody is partaking on a event then you can call them a participant. if somebody is attending regular meetings you can call them a member of the group or team,
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