I have bought "Mac book" :)
=> もっと普通な英語で: I (have) bought a 'Macbook'. <em>(You need to mention HOW MANY Macbook you bought; in this case, you bought just 1, so you need to specify it using "a" ==> "~a Macbook".)</em>
I finally got that "Macbook " :)
=> Were you longing for a Macbook for a long time? If you were, then you can also say, "I finally got that/the Macbook I was longing for!"
<em>*It's just my opinion; your sentence was perfectly fine too!</em>
I am writing in this notebook using the Macbook.
=> I am writing this notebook using the Macbook.
This PC is better than any I have ever used.
=> This PC is better than any other I have ever used. <em>(You need the 'other' since you are talking about a comparison WITH OTHER computers... )</em>
Skype ID ayaka04blue
Let's study with me :D
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Wow! うばらしい!Macbookは本当にすごいパソコンですよ!羨ましいなぁ~!でも、Windowsパソコンよりちょっと使い方かた難しいだと思います。でしょう!
英語もすごかったです。I mentioned the reasons for some of the corrections I made to your note. My corrections were to make your note more natural. Of course, what you wrote at first is totally comprehensible, so don't worry!
Macbookを楽しんでね!今新しいパソコンがもっているから、勉強をもっともっと頑張らないといけませんよ!(<-Since you've got a new PC now, you must study more and more!) ...ぼくは日本語がまだよくわからないと思いますので間違ったらなおしてくださいね!
それでは、またこんど。(^_^)/