How to spell it,please?To有什么用?为什么要加To呐?

How to spell it,please?To有什么用?为什么要加To呐?
How to spell it,please?To有什么用?
为什么要加To呐?

How to spell it,please?To有什么用?为什么要加To呐?
请问,该如何拼写呢?
To这里是放在疑问词How后面表示方式
TO [强 tu:, 弱 tu, 辅音前弱tə, t]




adv. 向前；（门等）关上
prep. 到；向；（表示时间、方向）朝…方向
【To 用法总结】
一：表示相对,针对
be strange (common, new, familiar, peculiar, distinct, sensitive, immune, vulnerable, indispensable) to
Air is indispensable to life.
Aircrafts are vulnerable to interference caused by radiation.
This injection will make you immune to infection
二：表示对比,比较
1：以-ior结尾的形容词,后接介词to表示比较,如：superior ,inferior,prior,senior,junior
The quarrel happened prior to my arrival.
2:一些本身就含有比较或比拟意思的形容词,如equal,similar,equivalent,analogous
A is similar to B in many ways.
3：表示一些先后顺序的形容词,如：second,subsequent,next,preliminary,preparatory
Subsequent to the war,they returned to their hometown.
4:to也偶尔出现在个别动词之后,与动词形成固定词组,表示比较,如:prefer to,compare to,in contrast to compare to sth.表示比喻或比拟,而compare with sth.表示比较,如:
World is usually compared to a stage
Compared with his past,he has changed a lot.
Prefer的正确句型是:prefer A to B或prefer doing A to doing B,但当prefer后接动词不定式时,表示比较的介词to就要改成rather than ,如:
The undaunted soldier preferred death to surrender.
Many people prefer spending money to earning money.
They prefer to pursue careers rather than remain home as house wives.
5:to与及个别的名词构成比较之意,如:alternative
Going to an under water concert is a great alternative to going to dinner.
三:表示修饰关系
1:表示回复,反应意思的词,如:answer to question,
solution to problem,response to inquiry,reaction to proposal,reply to letter
2:表示建筑构件的词汇,如: entry,entrance,approach,access,passage,exit,vent,path
the approach to a bridge引桥
the approach to science
Half of the population was estimated to have no access to the health service.
The access to education 接受教育的机会
The access to medical care 享受公费医疗的权利
4:表示人物职位和官衔的词,如:assistant to manager, ambassador to Spain, successor to tradition, heir to throne,deputy to the National People’s Congress
advisor to the Prime Minister
5:表示权利和许可的词汇,如:right,admission
The employee finally got the admission to the boardroom.
Everyone has an equal right to ……..
6:表示栅栏或障碍的词汇,如:bars to development,the barrier to progress
7:表示与书籍,文本相关的词,如:introduction to passage.
8:表示恭喜或是祝贺,如:
The director proposed a toast to the health of the guests.
Let’s drink to Dick’s success in business
9:另外还有一些名词符合这种用法,有的具有两者息息相关,缺一不可的含义.如:key to door,invitation to party,
guide to action,limitation to life,accessory to school
四:to还具有依据,伴随,和着节奏的含义,如:sing to piano, chance to the tune, stamp to the rhythm of the song, add salt to taste
五:表示趋势或倾向,如:tend to,be prone to,be inclined to,be apt to,be liable to
He’s liable to seasickness.
You are liable to come to wrong conclusion.
六:表示对事情的坚持与执着,如:sick to,hold o,adhere to,cling to
He still holds on to his original views.
七:表示约束,局限,如:limit to,confine to,resrict to
He’s confined to the house by illness.
He confined his remarks to scientific mangement.
八:表示一种习惯或是一种适应性,如:get (be) to,used to,be accustomed to
Finally,the students got used to my teaching method.
十:表示起因和原由,如wing to,due to,thanks to,attribute to,come down to
The flight was cancelled due to the thick fog.
The famous artist attributed his success to his wife.
十一:表示目的或结果,如:aim to,lead to,give rise to
I aim to be an excellent college teacher.
His conceit lead to his failure.
These bad condition has given rise to a lot of crises
十二:表示命运,注定,如:be doomed to,be destined to,
All military adventures by the two super powers are doomed to fail.
十三:表示数量上的积累或增加,如:in addition to,add to,amount to
In addition to relief supplies,he also presented with some money.
The annual output of steel amounts to 1200 tons.
十四:表示全身心投入的含义,如:be addicted to,contribute to,devote to,commit to
He is determined to devote all his life to his.
十五:表示展望或是回顾,如:look forward to反date back to
The church dates back to the 13th century.
十六:表示方位概念.如:close to,next to
I don’t like wool next to my skin.
十七:表示依靠或借助,如:resort to,turn to,appeal to,
He usually appeals to arms to settle the territory dispute.
十八:表示有关注,关于:as to,with regard to
十九:表示关注或重视,如:pay attention to,attach to,
We should attach primary importance to job training.
二十:表示依据或是根据,如:according to,in proportion to
According to today’s newspaper,the match will be postponed.
The lending countries subscribe towards capital stock in proportion to their economic importance.
二十一:表示应该或必须含义的句式,如:
It’s time to get up.
We are supposed to get here at seven.
It’s up to this country to ban nuclear weapons.
二十二：表示相关联,相连接,如：be related to,be relative to,in relation to,be relevant to,link to
Investigate all the facts related to the problem.
People often linked walth to happiness.
二十三：表示反对和赞同.
1：to引导的表示反对,抗拒,对抗意义的词组.Be opposed to,be oppsist to,be contrary to,be adverse to,be resistant to,be contradictory to,object to,oppose to,deny tp,be aline to
These buildings are resistant to earthquake.
They are to tally opposed to any changes being made in the plans.
2:to引导的表示同意,赞同意义的词组：consent to,subseribe to,
The employer consented to give him a salary raise.表示调整,使符合,使适应的含义,如：adapt to,commodate to,adjust to,conform to,habituate to,fit to,suit to,correspond to,cater to
She tried to habituate herself to the style of plain living.
Your action should conform to the interests of the people.
They offered various foods to cater to the need of customers.
His words doesn’t fit to his actions.
Suit your writing style to the masses.
3:表示投降,屈服,服从的含义,如:be subject to,be subordinate to,submit to,subject to,surrender to,give in to,confess to,admit to.
The minority is subordinate to the majority少数服从多数
Countries nearby oceans are always subject to earthquake.
He confessed to having robbed the woman of her wallet.
We’re not the kind of people to yield to any military threat.
常用词组
respond to（反应）,appeal to（吸引）,catch on to（理解）,listen to（收听）,used to（过去常常）,give birth to,attend to（照料）,see to（负责）,be entitled to（有权）,belong to（属于）,come to（苏醒）,stand up to（勇敢面对）,help oneself to（请自便）,refer to,to the point（切题）,
Train them to stand up to any severe test in hard.
The ticket entitled you to a free meal in the luxury hotel.
See to it that the children get a hot meal after their swim.
You will catch on to the job shortly after wards.
People usually refer to television for up-to-the-minute news
祝进步~
【英语精英联盟团】

请问如何拼写？这里to是介词 没有具体意思。