過去形と完了形について
過去形＝過去のことで、今の話し手の状況に影響していない。
完了形＝過去のことで、今の話し手の状況に影響している。
つまり、完了形を使うときは、そのことが主語である「私」の今に繋がっている場合に使われます。
例
I have decided to study abroad, now I am thinking about where to go.
留学するって決めたんだ！今どこに行くか考えてる。
I have not decided anything yet.
俺はまだ何も決めてないよ。
I have made up my mind, I am going to study abroad.
>I have made up my mind, I am going to study abroad.
*made up my mind = You have finally decided...
Example
Friend: So where are you going to study next year?
You:I have made up my mind, I am going to study abroad.
I have made up my mind, I am going to study abroad.
made up my mind = 最終的に決断すること。
例えば、下記のように使います。
Friend: So where are you going to study next year?
来年どこで勉強するつもりですか？
You:I have made up my mind, I am going to study abroad.
留学にいくことを決めました。
My decision is to study at Harvard University in the US.
You may put it succinctly and state your decision without mentioning the name of the university you are going to study at. This leaves your audience wondering as to which university in the US you are going to study at. However, in the second statement, you have again succinctly stated your decision, but, proceeded to mention the name of the university you are going to study at: Harvard University.
So, you may say:
I have decided to study in the US.
or
My decision is to study at Harvard University in the US.
勉強しようとしている大学の名前を言うことなく、自分の決断だけを簡潔に言うことができます。
そうすると、聞き手にとってはあなたがアメリカのどの大学で学ぶのかわからないままになります。
しかしながら二つ目の文章では、簡潔でありながらもハーバード大学に行くことが伝わります。
そこで、以下のように言えるかもしれません。
I have decided to study in the US.
アメリカで勉強すること決めました。
または
My decision is to study at Harvard University in the US.
アメリカのハーバード大学で勉強することを決めました。
I could have studied in my home country, but decided against it
Studying in one's home country sucks! It's not for me!
To decide against something = Meaning: to decide not to do something you were thinking of doing, or not to choose something or someone you were thinking of choosing.
It sucks! =Not good. Bad.
The early Jazz musicians would say that a guy could really "Blow" if he had a good sound when playing the horn. If he couldn't play very well then they would say that he was "Sucking" on that horn. That's where the term "Suck" as being something bad came from.
To decide against something = 自分の考えに反してしないことに決める。
自分の選ぼうとしたものに反して選ばない。
It sucks! =良くない！悪い！
初期のジャズ音楽家は、良い音を出してくれるホルン演者には"Blow"という動詞を使い、下手だったらsuckが使っていました。
これがSuckが悪い意味を持つようになった由来です。
I have decided to take the plunge and study abroad
I have opted to study abroad
"take the plunge" is a phrase used to describe a situation where you have made a decision to commit to something that is important and perhaps a little bit scary or very adventurous or requires a lot of commitment from you. e.g.
I have taken the plunge and asked Hitoe to marry me.
I will taken the plunge and buy a house.
"I have decided to take the plunge and study abroad."
The phrase in this sentence indicates it was a big decision to make as studying abroad needs courage to do.
"I have opted to study abroad"
Opted is a word that is used when you have a number of possible choices.
Opted is used to show you have considered all choices/options and then made your decision.
I have opted to study economics and not English.
"take the plunge"(思い切って～する)
というフレーズは、「緊張や恐怖を感じるけど大切な何かをすると決めた」ときに使うことができます。
I have taken the plunge and asked Hitoe to marry me.
（意を決してひとえに結婚を申し込んだ。）
I will take the plunge and buy a house.
（ついに家を買う決心をする。）
"I have decided to take the plunge and study abroad."
（私は海外に留学することを決めた。）
「留学することを決心するには勇気が要った」ということが相手に伝わる文章です。
"I have opted to study abroad"（留学することを選んだ。）
"opted" はいくつか選択肢がある中から選ぶときに使うことができます。いくつかの選択肢の中から一つを選んでその道に決めた、ということを伝えるフレーズです。
I have opted to study economics and not English.
（英語ではなくて経済学を勉強することに決めた。）
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