「…するつもりだ」と前から決めている予定は、be going to＋動詞の原形で表現できますが、さらに確定的な響きを伝える場合は現在進行形be -ingを用います。これで「…することになっている」というニュアンスになります。
I'm moving to the US at the end of next month.（来月末にアメリカに移動[移住]することになっています）
単純にgo toの現在進行形で言い換えてもOKです。
I'm going to the U.S. at the end of next month.（来月末にアメリカに行くことになっています）
以上、ご参考ください。
I am flying off to America at the end of next month.
I am going on a trip to America at the end of next month...
Travel and letting people know your plans can be essential, especially when planning schedules and meetings with friends and collegaues.
So, its good to have a concise and clear way to communicate that...
PS Using a specific date would end any "uncertainty" regarding your journey
and leave no doubts as to your actual plans...
I am going/relocating/moving to America at the end of next month.
Depending on what you are going to do in America you can say you are relocation/going/moving. In place of "next month" you can also specify the month. For example August or you can even tell them the exact date (26th of August)
I plan to go to America in the latter part of next month
I'm off/I'm off to - this isn expression used informally when you want to state that you are going somewhere.
"Well, it's been a great evening guys, but I've had too much to drink and now I'm off home."
To plan to go somewhere - if you have a firm plan which you intend to carry out you may state that you 'plan to do' something.
"I plan to stay with my aunt Edith for a week before seeing the rest of my relatives."
I'm off/I'm off to -自分がどこに行くか言いたいときに使えるカジュアルな表現です。
"Well, it's been a great evening guys, but I've had too much to drink and now I'm off home."
すごく楽しい夜だけど、飲みすぎてしまったから、家に帰るよ。
To plan to go somewhere -自分が何かしたいことがあるというときは、 'plan to do' something'も使うことができます。
"I plan to stay with my aunt Edith for a week before seeing the rest of my relatives."
他の親戚に会う前に一週間、叔母のエディスのところに泊まる予定です。
you can say "end of" + name the month
the US, the States, America, the USA - these are all shorter ways to say the United States of America. Personally, I tend to say the States and sometimes the US
A. When are you taking your trip to the US?
B. Well, I'm too busy this month, but I'll be going at the end of August, more than likely.
A. Have fun!
"end of" + 月で ”○○月の終わり” という意味になります。
the US, the States, America, the USA - これらはアメリカの呼び方ですが、省略して "US" とだけ言っても伝わります。
私はだいたい”The States”を使いますが、時々”The US"とも言います。
例
A. When are you taking your trip to the US?
（いつアメリカ旅行行くんですか？）
B. Well, I'm too busy this month, but I'll be going at the end of August, more than likely.
（今月は忙しいのですが、多分８月の終わりに行くと思います。）
A. Have fun!
（楽しんで来てください！）
I am going to America at the end of the next month
Next month I am going to America.
When you want to explain that you are going to America at the end of next month, then you can say it in the following ways:
-I am going to America at the end of the next month
-Next month I am going to America.
Remember it might be helpful to be more specific whether you are moving to America indefinitely or only visiting on your vacation. If it's a mere visit, then rather use "visiting" instead of going because it makes it clearer.
来月末にアメリカに行くことを伝えたいなら、以下のように言えます：
-I am going to America at the end of the next month
（来月末にアメリカに行きます）
-Next month I am going to America.
（来月アメリカに行きます）
アメリカに引っ越すのか、それともただ休暇で訪れるだけなのか、もっと具体的に言った方がいいかもしれません。単純に訪れるだけなら、「going」ではなく「visiting」を使った方が、より明確になるので、いいと思います。
I am going on vacation to America at the end of next month.
I am moving to America at the end of next month.
If you want to explain that you are going to America at the end of next month, you can say:
"I am going on vacation to America at the end of next month."
"I am moving to America at the end of next month."
「来月末にアメリカに行きます」は次のように言えます。
"I am going on vacation to America at the end of next month."（来月末に休暇でアメリカに行きます）
"I am moving to America at the end of next month."（来月末にアメリカに引っ越します）
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