感到, 觉得, 认为, and 以为

In this post, we are going to talk about the difference among 感到, 觉得, 认为, and 以为. 

感到 (gǎndào, feel/be) + inner attitude or feeling received from the outside world

• 听说UB会有一个表演, 他感到很好奇。It is said there would be a performance at UB. He feels very curious.
• 他看这部电影的时候，感到心脏跳得很快。When he saw the movie, he feels his heart beating fast.
• 阳光那么暖和，她感到很舒服。The sunshine is so warm that she feels very comfortable. 

觉得 (juédé, feel/think) + a feeling from senses or a thought or opinion in one's mind

• 虽然今天下雪，可是他觉得一点儿也不冷。Even if it is snowy, he feels it is not cold at all.
• 他觉得这个问题一点儿也不难。He thinks this question is not difficult at all. 

认为 (rèn wéi, think, believe) + objective reflection and reasoning, which is usually used in written language or formal situation like lecture or academic discussion. For example, 

• 我认为你是对的。I think you are right.
• 我认为学一门外语很有好处。I think learning a foreign language is beneficial. 

以为 (yǐ wéi) + something you thought so, but in fact it is not. 

• 我以为你是中国人。 I thought you were Chinese. ( so bad, I make a mistake)
• 我以为他没有女朋友－I thought he didn't have a girlfriend. (but he actually does)

Please fill in the blanks by using 觉得, 感到, 认为, or 以为 
1. 我______她很可爱。　I think she is so cute[this is my opinion]
2. 我______你是一个好人。 I thought you were a good guy. (but now, I don't think so) 
3. 我______你是一个好人。 I Believe you are a good guy.
4. 我______你是一个好人。 I feel that you are a good guy. (not so sure, just a feeling)
5. Dialogue
A: 我是加拿大人。(I'm a Canadian.)
B: 真的吗？我______你是美国人。(Really? I thought you were American.)
A: 不是，我住在多伦多。(No, I live in Toronto.)
6. Dialogue
A: 今天我_______很不舒服
B: 你是不是感冒了? 


Please translate the following sentences.
1. 我以为认为和以为的意思相同。
2. When she heard that her friend is coming to visit her, she felt very happy.
3. He think this book is very interesting but she doesn't think so.
4. She's sick, so I don't think she will come today.
5. I thought she would not come, but she is here. 
6. I feel this room is so hot. Could you please open the window?

Reference:
http://www.italki.com/question/3815
http://write.scu.edu.tw/file/pei/4-2.pdf.