I. Lizzy's first impression of Mr. Collins 
      After the arrival of the letter from Mr. Collins, Lizzy found that Mr. Collins was a bit self-important and conceited; it seemed that his words were ambiguous and uncertain. "There is very something very pompous in his style. And what can he mean by apologizing for being next in the entail? We cannot suppose he could help it, if he could." (ch.13 p.44) However, when they finally met, Lizzy didn't have particularly negative impression toward Mr.Collins. She still kept her courtesy to treat him as a common guest. For instance, when Mr. Collins read a book making them bored and impatient, Lizzy advised against Lydia's impolite interruption timely. Basically, Lizzy had no favor or disfavor to him.

II. Lizzy's response to the proposal of Mr. Collins 
     As everybody knows, Lizzy refused Mr. Collins. From Mr.Collins's declamation about the reason why he wanted to marry her, she felt he was not asking but informing her the fact that they were going to marry. He had already arranged everything without considering her feeling. Besides, he was too overweening to believe that he was indeed rejected by her. He even thought her rejection was just out of coyness. "Your refusal of my addresses is merely words of course... you are not serious in your rejection of me, I shall choose to attribute it to your wish of increasing my love by suspense, according to the usual practice of elegant females." (ch.19 p.75, p.76)That really irritated Lizzy. She thought it was hard to communicate with Mr. Collins because he always stuck to his own opinion instead of listening to others.

III. Lizzy's first impression of Mr. Darcy 
     The first time she met Mr. Darcy was in Meryton ball. He looked arrogant because he seldom talked to other people and wore no smile on the face. He seemed indifferent to everything in the party. Moreover, Lizzy heard Mr.Darcy's statement of herself, "She is tolerable; but not handsome enough to tempt me; and I am in no humor at present to give consequence to young ladies who are slighted by other men..." (ch.3 p.9) She felt not to be respected; meanwhile, it was rude to comment on a lady this way, especially not what a gentleman should do. Since then, she had bias against Mr.Darcy from his entire attitude that night. "From the very beginning, from the first moment of my acquaintance with you, your manners impressing me with the fullest belief of your arrogance, your conceit, and your selfish disdain of the feelings of others..."(ch.34 p.131)

IV. Lizzy's response to the proposal of Mr. Darcy 
     When Mr.Darcy expressed his love and made the proposal to Lizzy, she felt so astonished that she didn't react immediately. After a long pause, she thanked him for his compliments and declined his request. Besides her first impression to Mr. Darcy, she remembered what he had done to her sister, Jane. But the most detestable point was that he should be satisfied with that. "I have no wish of denying that I did everything in my power to separate my friend from your sister, or that I rejoice in my success." (ch.34 p.130) Her decision was also based on what Mr.Wickham said about Mr.Darcy, "He had not a temper to bear the sort of competition in which we stood--the sort of preference which was often given me..." or "He can be a conversible companion if he thinks it worth his while. Among those who are at all his equals in consequence, he is a very different man from what he is to the less prosperous."(ch.16 p.55) She had never thought of marrying him for those succeeding events happened had built so immovable a dislike to him. "I felt that you were the last man in the world whom I could ever be prevailed on to marry."(ch.34 p.131)

V. Conclusion 
    Lizzy's decision to refuse Mr.Collins's proposal is right. Mr.Collins chooses his wife in terms of advantage, not of emotions. In the beginning he wanted to marry Jane; after failed, he turned his attention to Lizzy; again being rejected, he soon found another woman, Charlotte. It has proved that he doesn't get married for love. Marrying such a man will not bring her happiness.

    However, the other decision to refuse Mr.Darcy is obviously wrong. She is affected by the first impression of Mr.Darcy. The prejudice against him has been deeply rooted in her mind. The most foolish thing she has done is to trust Mr.Wickham. She is too infatuated with him to tell good from bad. Most important of all, the reason why Lizzy refuses Mr.Darcy is not because she doesn't love him. Probably she hasn't found it, but she gives no chance to think about it.

    Fortunately, Lizzy starts to face the fact that maybe she has misunderstood Mr.Darcy after reading the letter from him. She recalls the way they get along with each other, "She observed his increasing civilities toward herself, and heard his frequent attempt at a compliment on her wit and vivacity..."(ch.17 p.61)and Mr.Wickham's contradictory conduct. What he said didn't correspond to what he did. Even the criticism of her family is hard to refute. She finally admits that she is too assertive and blind. "How despicably have I acted! I, who have prides myself on my discernment! I, who have valued myself on my abilities! How humiliating is this discovery!"(ch.36 p.141)From the example of these two proposals and Lizzy's attitude, we can see clearly how a wrong first impression could change our decisions, and how dangerous it may be if we jump to conclusions when judging anything.