while&whereas做连词区别
1.The system provides a way for companies to remain globally competitive _______ avoiding market cycles and the growing burdens such as healthcare costs and pension plans.
A) but B) while C) whereas D) and
2.He thought I was lying,______ I was telling the truth.
A) while B) whereas C) therefore D) however
以上两句话答案都是B,但是区别在哪里?都做连词,而且都可以引导句子表示转折和对比,