My dad is on vacation in the States and he's coming back next week.
My father has gone on a trip to the US and he will come back next week.
Dad left on a trip to America yesterday, and he'll be there until next week.
こんにちは。
・My dad is on vacation in the States and he's coming back next week.
「お父さんは休みでアメリカに行っていて、来週帰ってきます」
・My father has gone on a trip to the US and he will come back next week.
「父はアメリカに旅行に行っていて、来週帰ってきます」
・Dad left on a trip to America yesterday, and he'll be there until next week.
「パパは昨日アメリカ旅行に旅立って、来週まで向こうにいます」
上記のような言い方ができます。
ぜひ参考にしてください！
My father left yesterday and will be back next week from the USA.
My dad is only away in America for a week or so, and will be back next week.
Throughout most of the world the United States of America is known just as the USA, whereas in Britain most people just refer to the USA as America.
When we say a week 'or so' this means that your father is away for around a week, so it may be 6 days, or more than a week, like 8 or 9 days.
世界のほとんどのところで、アメリカは "the USA" と呼ばれますが、イギリスではほとんどの人が "America" と言います。
"a week or so" は、お父さんがだいたい1週間（6日間か一週間以上か、例えば8日間とか9日間とか）旅行に行くことを表します。
Yesterday my dad left for his trip in America, he'll be home next week.
"Yesterday my dad left for his trip in America, he'll be home next week."
Simply saying, you are telling the other person your dad went to America yesterday and that he will be home in 7 days (a week).
"Yesterday my dad left for his trip in America, he'll be home next week."
（父は昨日アメリカ旅行に出かけました、来週帰って来ます）
お父さんが昨日アメリカに旅立って、7日後（一週間後）に戻るということを伝えています。
My dad went on a trip to America yesterday, but he's coming back next week
Yesterday my dad left for a trip to America, he will return next week
If you come back from somewhere then you are also said to 'return' to explain your dad went to America on a trip yesterday then you can say 'my dad went on a trip to America yesterday' or 'yesterday my dad left for a trip'
どこかから戻ってくることは、'come back' の他に、'return' でも表せます。
「父は昨日アメリカに旅行に行った」は、'my dad went on a trip to America yesterday' または 'yesterday my dad left for a trip' と言えます。
My dad went on a trip to America yesterday, and he’s coming back next week.
My dad went on a trip to America yesterday, and he’s coming back next week.
父は昨日アメリカへ旅立って来週帰って来ます。
質問文をそのまま訳すと上記のようになりますが、「旅行に行っている」状態を言うのであれば、
He’s on a trip to America right now.
彼は今アメリカ旅行に行っています。
でいいと思います。
"My father went to the US yesterday but he will be back next week."
"My father left for the US yesterday and he will be back next week."
"My father went to the US yesterday but he will be back next week." Depending on the situation you might use "but" in the sentence. If someone is asking to speak with your father but he is not there at the moment, you are letting them know when he will be back.
"My father left for the US yesterday and he will be back next week." "Left for" is used to explain you have gone somewhere, from one city to another, for example 'I have left Sydney for Perth'. In this example sentence you say "and he will be back" simply to provide that information as well, not necessarily because someone is directly asking when your father will be back.
"My father went to the US yesterday but he will be back next week."
（父は昨日アメリカに行って、来週帰ってきます。）
状況にもよりますが、この文では "but"（~だが）を使うといいかもしれません。もし誰かがあなたのお父さんと話しがしたいけれど、今いなくて、いつ帰ってくるのかを伝えることができます。
"My father left for the US yesterday and he will be back next week."
（父は昨日アメリカに出発して、来週戻ってきます。）
"Left for"は、～に行くという意味で、 例えば 'I have left Sydney for Perth'（パースに向けてシドニーを出発した）のように使います。 "and he will be back" は、誰かがお父さんがいつ帰ってくるのか聞いていなくても、情報として伝えることができます。
My father's on vacation in America, but he'll be back next week.
By using synonyms such as 'trip', 'holiday' or 'vacation', you are automatically indicating that whilst your father has gone, he will most definitely be returning.
To explain your situation fully, you would be best to use a number of sentences.
"My father left on a trip to America yesterday. He is taking a week-long vacation. He'll be coming back next week."
The use of the grammatical construction "has gone" is also an indication that a person has left but intends to return.
EG: "He has gone to the supermarket."
"He has gone to America."
If the person was not intending to come back, we would use the past simple construction, 'went'.
EG: "He went to America. He now has a family there."
trip' や 'holiday' 'vacation' を用いることで、お父さんが「今はいないけど、いずれ戻ってくる」ことが伝わります（'trip' 'holiday' 'vacation' は同義語です）。
この状況を完全に説明するなら、いくつかの文に分けた方がいいです。
"My father left on a trip to America yesterday. He is taking a week-long vacation. He'll be coming back next week."
（父は昨日アメリカに旅行に行きました。一週間の休暇を取っています。来週戻ってきます）
"has gone" でも、「今はいないけど、いずれ戻ってくる」を表せます。
例：
"He has gone to the supermarket."（彼はスーパーに行っている）
"He has gone to America."（彼はアメリカに行っている）
その人が戻ってくるつもりがないなら、過去形の 'went' が使えます。
例：
"He went to America. He now has a family there."
（彼はアメリカに行きました。今は向こうで家庭を持っています）
My father left to the US yesterday and will come back next week.
My father left to the US yesterday and will come back next week.
父は昨日アメリカに旅立ち、来週帰ってきます。
様々な表現の仕方があると思いますが、上記はいかがでしょうか。
left to the US で「アメリカに旅立った」ようなニュアンスになります。
お役に立てれば嬉しいです。
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