It has been two weeks since I have spoken English.
You want to use the present perfect tense (it has been, spoken) because you still are continuing to not speak English. When you want to talk about how long it has been since you have done something the phrase is "it has been (period of time) since."
I hope that this helps :)
あなたが今も英語を話していない状況が続いているので、現在完了形 (it has been, spoken)を使うといいでしょう。あることをして以来どのくらい経ったかを伝えるには、"it has been (期間) since."を使います。
I haven't had the opportunity to speak English for two weeks!
It's been two weeks since I last spoke English.
As we know, sometimes we don't have the opportunity to practice the language we are learning. We may be in a different place, or maybe we just can't practice much besides in our English classes.
If we want to talk about this, we can use some expressions such as:
1) I haven't spoken English in two weeks.
2) I haven't had the opportunity to speak English for two weeks!
3) It's been two weeks since I last spoke English.
ご存知の通り、時々、私達が学んでいる言語を実践する機会が得られません。別の場所にいるかもしれないし、または私達の英語のクラス以外ではあまり実践できないかもしれません。
このことを言いたいなら、以下のように言えるでしょう:
1) I haven't spoken English in two weeks.
2) I haven't had the opportunity to speak English for two weeks!
3) It's been two weeks since I last spoke English.
（2週間英語を話していません。）
Or you could say 'I haven't uttered a word of English in two weeks.' Both these sentences are standard ways of expressing yourself in American English. 'Utter' means the same as speak, but is usually used in instances like this one (to emphasize the lack of words) -- e.g.: 'He uttered only three words during the speech: 'all is well.''
もしくは、"I haven't uttered a word of English in two weeks." (二週間英語を一言も話していません) と言うことも可能でしょう。アメリカ英語ではこれらどちらの文も、自分の考えを表す標準的な言い方です。"utter" (言う、口にする) は "speak" (話す) と同じ意味ですが、これは普通、(言葉が足りないことを強調する) このような例で使われます。
例：
'He uttered only three words during the speech: 'all is well.''
〈訳〉彼はスピーチで三つの言葉しか発しませんでした：'all is well.' (全て順調です)
In foreign countries, we may reduce the amount of time spent speaking our home language. Or, we may have extended periods of time when we only use the second language.
If you have not done something for a while then you would say 'i haven't' by adding 'in two weeks' this explains how long it has been since you done it
you could also use the amount of time by saying 'it's been two weeks since'
何かをしばらくしていないなら、'I haven't' が使えます。
'in two weeks' は、それをどのくらいの間していないのかを示します。
他に、'it's been two weeks since'（～してから2週間たった）という言い方もできます。
This is the first English I am speaking in two weeks
It has been two weeks since I last spoke English
If you now are explaining this fact in English we can assume the two weeks are in fact over! You can explain this in the present continuous tense, "this is the first English I am speaking...".
Adding "...in two weeks" explains the time lapse in which you have not spoken English.
You could also use the present perfect tense to say "It has been two weeks..." to talk about how much time has passed since you last spoke in English.
2週間英語を話していないことを伝えたいということは、きっともう英語を使えているんですね！このことを伝えるには、現在進行形を使って以下のように、言うことができます。
"this is the first English I am speaking..."
（これがしばらくぶりに話す最初の英語です。）
"...in two weeks" を付け加えることで、2週間ぶりにという意味になります。
また現在完了形を使って、"It has been two weeks..."（2週間経った）と、最後に英語を話してから2週間が経ったことを伝えることができます。
"I haven't practiced my English for two weeks.": Practice means to carry out an activity on a regular basis in order to improve in it, and practiced is the past tense form of this verb. Therefore, this sentence means that you haven't spoken English in a regular way for two weeks.
"It's been two weeks since I spoke English." 'Since' is an effective way of marking how has passed. For example, you can say "It's been a year since I saw my friend". In this context, it means that the last time you spoke English was two weeks ago.
"I haven't practiced my English for two weeks."（2週間英語の練習をしていません）
'Practice' は上達するように繰り返し習うことをいいます。'Practiced' はこの動詞の過去形です。ですから、この文は「2週間英語の練習をしていない」という意味です。
"It's been two weeks since I spoke English."（最後に英語を話したのは2週間前です）
'Since' は経過した時間の長さを示す効果的な言い方です。例えば、"It's been a year since I saw my friend"（最後にその友達に会ったのは1年前です）と言えます。ここでは、「最後に英語を話したのは2週間前」と伝えています。
I haven't practiced my English speaking in two weeks.
Last time I practised English speaking was two weeks ago.
It is more correct to use the last two sentences because you will be speaking English when you say the words which means that it will no longer be two weeks since you spoke English, it will be that you have just spoken English.
It is more correct to say 'practiced English' instead of spoke or spoken.
This makes it more clear that you are talking about your learning the English language.
"I have been so busy with work and home life that I haven't practiced my English speaking in two weeks."
これは二つ目と三つ目の文がより正確です。なぜかというと、この発言をするときには英語を話すわけなので、もう2週間ではなくなりますよね。
'practiced English' と言う方が 'spoke' または 'spoken' と言うよりも正確です。
こうすると、英語学習について言っていることが明確になります。
"I have been so busy with work and home life that I haven't practiced my English speaking in two weeks."
（仕事や家のことで忙しくて、ここ二週間は英語の勉強ができていない）
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