DMM英会話を始めて3カ月です。って英語でなんて言うの？

1. Here, I have used the present perfect continuous to describe an action that began three months before and is still in progress. This is perhaps the most natural way I would express this idea to someone if I wanted them to understand that I'm still taking the lessons. 2. In this sentence I use the simple past because I want to stress the time I began the classes. It is perhaps assumed that I continued with them (maybe I didn't!) but the main point here is about when I started them. 3. In this sentence, by using present perfect, I'm stressing that I began the classes three months ago and have continued up to now. I don't really state that I'm continuing with the classes (I might be though) as here, the message is simply about how long I'v studied for

These sentences are stating that one has recently joined/signed up to 'DMM Eikaiwa', To 'start' something is the term used when you have began a process of an activity etc. you are at the very beginning of it unless it is followed with a time period, ex. "I started running 2 weeks ago" "I started cleaning my house".

You want to use the present perfect (I have) because this is an action that started in the past and is continuing to happen in the present. You can take lessons for many different things, including English. I hope that this helps. :)

We use the grammatical structure of "have been learning" as a way to explain an action that began in the past and continues to the present day. In this case, what began in the past was learning, and it is still happening now. Any action like this is explained with have - been - verb + ing. If a new student wishes to say this in a simpler way, they can simply say "have been using" and it is implied that through use of an English school, the student is learning English. Also, it is acceptable to start by explaining the timeline and then say "I started" as a way to indicate when classes began.

This let's someone know how many months you have been taking English lessons. You can also be very simple in your speech by saying, I just recently started lessons. You can give a frame of time (3 months) if the person asks "how long". Normally, speaking as a native, we would just say, I've been with DMM for three month. Or, you can rephrase it to say, "Three months ago, I started taking English lessons."

When you want to explain that you have been with DMM Eikaiwa for three months; then you have may explain this in the following ways: -It has been three months since I started taking classes at DMM Eikaiwa -I've been taking classes at DMM Eikaiwa for three months now