なぜすべて英語で話しているかというと留学に行くからです。って英語でなんて言うの？

"On a daily basis" is often used to express a consistent behaviour or to reiterate that something will become a habitual practice.
In this case, since the student is going off to an English speaking country to study he feels the need to get into the habit now and start to speak in English CONSTANTLY...IE EVERY DAY... ALL DAY!
I will be speaking in English constantly (and on a daily basis) because I am going to Canada to study and I must start practicing now!

You are always speaking English. Why? What happened?
Well, I am going to study in Canada soon, so I am speaking only English at the moment.
That makes sense.
Thanks for understanding.

I hope this helps.
Have a good day.
Will

Using the phrase: I am always speaking in English now, means that English is the only language which you are using at the moment. Since you are going to be living/studying abroad in an English speaking country it is important that you practice all the time.

We use "from now on" to describe something that will happen from the moment you say it. You are thus saying that from that exact moment you will only speak to people- and answer people- in English. The second sentence you will use when you already started to just speak English and need to explain to other people. Hope this helps!

If you would like to explain to someone that you are only speaking in English to practice before moving to Canada to study abroad, you can say something like "I'm speaking only in English to practice because I will be going to study abroad in Canada soon.". This is a good way to explain this to someone.

To be practicing for something means that you are preparing for it. You will have to speak English in Canada therefore by practicing speaking English now, you will be prepared for it.
Both of these sentences explain why you are speaking English all the time. It is because you are going to Canada soon and will have to speak English there.

1. I'm off to Canada soon, so from now on I'm only going to
   speak English because I need the practice.
   ''Off to...'' means going to a place either to live, study or vacation.
   ''From now on...'' means from right now or from today.
   This is a good sentence to use because it is telling the listener
   that you do not want to speak in any other language, i.e. Japanese
   in this instance as you would like to have a better command of the
   language, improve your pronunciation and have more vocabulary at
   your disposal, by the time you reach Canada.

2. In preparation for my stay in Canada, I have decided to practice
   by speaking only in English.
   ''In preparation for...'' means that you want to prepare for your stay
   and your studies in Canada by building up your vocabulary and improving
   your pronunciation.

I'm only using English right now, because I will be in Canada soon, and need to practice. "Using English" is a common way native speakers use to mean speaking English. "Right now" is a common way to say now.

I am speaking only in English now, because I'm going to study in Canada soon.
This explains to people why you are talking to them in English.

You could use any of the above two sentences when telling someone that you are going to study abroad and that you need to practice your spoken English.

• I speak English regularly; means that you speak it often, almost everyday.
• I speak English daily; means that you speak the language everyday.

In these two sentences, we have the option to mention that we are speaking English only because we want, "to practice," before an event like moving to Canada. If you don't include this the sentence still makes sense as it would be a given within the context.