1. 没有多给您写信,实在抱歉。I certainly owe you an apology for not writing more often.
2. 他们大多数人都很友好，我也结交了一些好朋友。
The majority of them are really friendly and I have made some good friends.
3. 我一直忙于学习，了解身边的新事物、
I have just been so busy studying and trying to absorb all the new things around me.
4. 我很高兴你能抽时间来看我。I’m just so glad you can afford to visit me
