apply for = make an application for; make a request for 

apply to = put to practical or specific use (i.e. knowledge, laws, regulations);
                  deal with, refer to

직업or과정
1~ (to sb/sth) (for sth)to make a formal request, usually in writing, for sth such as a job, a place at college, university, etc.

ex)

to apply for a job / passport / grant

to apply to a company / university

He has applied to join the army.

이용하다or적용하다

2[vn]~ sth (to sth)to use sth or make sth work in a particular situation 전치사 to이겠죠

ex)

to apply (to) economic sanctions / (to) political pressure

The new technology was applied to farming.

페인트 or 물감 or 크림같은것을 바르다, 칠하다. 적용하다.
3[vn]~ sth (to sth)to put or spread sth such as paint, cream, etc. onto a surface

ex)

Apply the cream sparingly to your face and neck.

The glue should be applied to both surfaces.

적용되다

4(not used in the progressive tenses)~ (to sb/sth)to concern or relate to sb/sth

ex)

Special conditions apply if you are under 18.

What I am saying applies only_=nim style="FONT-SIZE: 10pt; FONT-FAMILY: Verdana"> 

The word ‘unexciting’ could never be applied to her novels.

열심히 하다. 전념하다
5[vn]~ yourself (to sth / to doing sth)to work at sth or study sth very hard

ex)You would pass your exams if you applied yourself.

We applied our minds to finding a solution to our problem.

압박or힘, 영향 을 주다
6[vn]to press on sth hard with your hand, foot, etc.

         to make sth work or have an effect on sth

ex)

to apply the brakes (of a vehicle)

Pressure applied to the wound will stop the bleeding.
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