. School is open 与 the school is open ：
school is open ( 或 schools are open) 是指‘学校开学’ (classes are in session) ，这里的 open 是形容词， school 前面不加冠词 the ，意味整个中小学的 school system 。但是 the school is open ，多指学校的建筑物开放着，但没有学生上课。
同理： He goes to school. 是指他去上学读书受教育，而 He goes to the school. 又指他去学校的建筑物（看朋友、参观等）。
但是 The store is open. 是指店在营业中（ = Business is going on. ），而 The store is closed. 又是指店 暂时不营业。假如店是永久性的‘关门大吉’，就应该说： The store was closed down. (permanently)
不过 closed 当形容词时，又有‘保守’（ conservative ）或受某种‘限制’（ restricted ）的意思。 例如：
This is a closed community. （这是一个保守的社区。）（由于宗教信仰等原因，美国有的社区不欢迎外来的人。）
2. Thick skin 与 thin skin ：
thick skin 是指一个人不害羞，冷静，好脾气 (insensitive,calm or good temper) ，但是 thin skin 是指很敏感 (very sensitive) ，易发怒，易激动的人。 例如：
He has thin ( 或 thick) skin. ( 当名词用 )
= He is thin-skinned ( 或 thick-skinnd).( 当形容词用 )
Many American politicians are very thick-skinned. ( 许多美国政客是冷静不易发怒的。 )
thick skin 不是咱们中国人所谓‘厚脸皮’‘不要脸’的意思。对老外来说，往往还是一种恭维呢！而 thin skin 恰好又相反。
3. To turn the tables 与 under the table ：
turn the tables 意思是扭转局面，作出反击或反告（ to turn around or to reverse the accusation toward accuser ），但是 under the table 是指做贿赂等违法的事情（ do something illegal ）。 例如：
In court she turned the tables of prosecution toward him. （在法院她反而控告他。）
Some politicians accepted brides under the table. （一些政客违法地接受贿赂。）
4. To be attracted to 与 to be attracted by ：
这都是指‘被吸引住’，不过介系词用 to 时，后面通常不说理由，但介词用 by 时，后面多半说明吸引的原因。 例如：
She was attracted to him. （她被他吸引住。）（但没有说明原因 ）
= She found herself attracted to him.
= He attracted her. ; 说白些，就是
= She liked him.;
同理 He was attracted to her.( 他被她吸引住。 )
= He found himself attracted to her.
= She attracted him.; 也就是：
= He liked her.
但是如果说：
She was attracted by his good-look. ( 她被他的英俊外表吸住了。 )
He was attracted by her beauty ( 或 charm 或 body). (always) ( 他被她的美貌或身材而吸引。 )
就是因为用 by 时，后面多半都说明吸引的理由。
5. Talk back to (someone) 与 turn (one's) back on (someone) ：
to talk back to someone 意思是对某人‘回嘴’（ to defy ），多半指小孩。而 to turn one's back on someone 系指不喜欢某人（ dislike someone ）。例如：
the boy talks back to his mother all the time. （这男孩对他母亲老是回嘴。）
至于 to be on （ one's ） back about （ something ）又有对某事‘唠叨’ (nagging )的意思。 例如：
His mother is always on his back about diet. （他妈妈常为了饮食对他唠叨。）
