【正确答案】：
ASSOCIATIVE MEANING IS THE SECONDARY MEANING SUPPLEMENTED TO THE CONCEPTUAL MEANING. IT HAS FOUR TYPES: CONNOTATIVE, STYLISTIC AND COLLOCATIVE. IN THE ABOVE TWO SENTENCES, THE ITALICIZED WORDS AHVE THEIR AFFECTIVE MEANINGS. IN SENTENCE A) AMBITIOUS IS OBVIOUSLY USED IN GOOD SENSE SHOWING APPROVAL ON THE PART OF SPEAKER, WHILE IN SENTENCE B) AMBITION CONVEYS A PEJORATIVE OVERTONE. SO, AFFECTIVE MEANING OF A WORD DEPENDS ON THE CONTEXT WHERE THE WORD IS USED. 
【题目解析】：联想意义是附加于概念意义上的第二重意义。它与概念意义的区别在于其开放性和不确定性。联想意义包括四种类型：内涵意义、文体意义、感情意义和搭配意义。在以上两个句子中，斜体字具有情感意义。在a句中，“有野心的”显然是在很好的意义上使用的，表示说话者的赞同；而在b句中，“野心”则表达了一种贬义的暗示。因此，一个词的情感意义取决于该词使用的语境。