I use the pen ________a letter?填什么?to write

I use the pen ________a letter?填什么?to write I use a pen to write.还是I use a pen to write with.为什么? I often write letter to my pen friend. I write ___ a pen .应填什么?（A.in B.with C.by D.use） The boy (writes/to write)the letter needs a pen.为什么用to write I want to use your pen.Could you p_________ in to me?应该填什么 Write a letter to pen friend saying I'd like to write a letter ___ my friend ___ America.中间空格填什么 The letter is___in Arabic.I cannnot read it.用write去填,用什么形式 I need a pen and some paper.I want to ____ a letter.A:write. I wanted to write a letter just now.So I wanted a pen.(改为同义句 I wanted to write a letter just now .So I wanted a pen .(同义句