positive: afraid adj. 害怕、恐怕 常用于be ~ to do sth. 害怕做某事 be ~ of (doing) sth恐怕 worry v.担心 常用 ~ about
negative: 一、and、or:<br>其实中文意思就可以区分清楚,and是和,并且的意思,or是或者的意思.你搞清楚它们之间的逻辑关系就自然明白了.While作并列连词用,意思为“而,然而”,表对比.而but表转折.注意用心比较体会while与but的句中用意;<br>二、but、while:<br>While作并列连词用,意思为“而,然而”,表对比.而but表转折.注意用心比较体会while与but的句中用意<br>1.Some people waste food while others haven't enough.<br>有些人很费粮食,然而有些人却吃不饱.<br>2.The son was having a good meal at home,while the parents were working in the fields.<br>儿子在家吃好饭而父母却在田里辛勤劳作.<br>3.I ought to have helped her,but I never could. 我本该帮她但没能.<br>4.Honey is sweet,but the bee stings. 蜂蜜很甜,但蜜蜂有刺蜇人.