sick in bed Can I use the phrase "sick in bed" if someone is in the hospital? or I can use it only the case if someone is in the bed of his/her house?) for example, is "He is sick in bed at the hospital." OK?

How to use "many" I am studying English grammar with a grammar book (written in Japanese), and I found the following explanation. == "many" or "much" is usually used in the negative sentence or the interrogative sentence. == Is it true? I often use "many" in affirmative sentences, like "I have many friends." or "There are many books in the library." Are these sentences awqward? Please help me.

What do you call my job in English? I work at home. I want to know what do you call my job in English. My job is correcting papers from school students. Once or twice a week, the correspondence education company send me students' papers to me. I correct them by the dead line, and return them to the company again. I mark ○ or ×　on the papers. If students made mistakes on their paper, I give some advice on the paper with a red pen. Also I score their papers. In Japanese, we call it "添削指導（てんさくしどう）" or "添削（てんさく". I always say like 「わたしは添削の仕事をしています。」 In English, how do you call this kind of job? Is "My job is cprrecting paper." make sence? Or do you have any particular name for this kind of job? Please help me.

About Quotation Mark In US & UK I really don't understand this problem. I read both US books and UK books. I noticed one thing. In US, they use " " when someone talks. (double) On the other hand in UK, they use ' ' . (single) Why does this happened? It is strange that the doble became single when it arrived from UK to US. I know that UK books use single and US books use double. But why did the difference happened? Do you know any historical reason?

abbribiation Can I write this way? Kate is my sister. Kate's my sister. (Can I use 's in this sentence?)

Writing telephone number If I write a telephone number in English, can I use hyphen in the sentence? It seems that using comma is the best, but can I use hyphen? "My phone number is one two three four, five six seven eight." may be good, but can I write "My phone number is one two three four - five six seven eight."?

How to use " " and ' ' Is there any differences between these scentence? It means "flower". It means 'flower'. Can I use " " or ' ' in the same way in this sentence?

"What is your favorite subject?" If someone asks me "What IS your favorite subject?", and I have two or three favorite subjects, can I answer two or three? for example," They are music and math." or " My favorite subjects are music and math". Or I just answer only one subject?

How to use　"not　so　well" "He plays basketball not so well." Does this　sentence grammatically　correct? Is this almost same　as "He is not very　good at basketball."　or　"He　doesn't　play　basketball　very　well."?