전치사 at

시간의 at(비교적 구체적인 시점)

at seven

at seven o'clock

at dawn 새벽에

at christmas

at seven o'clock

at twelve

at sunset

at Easter

at seventeen

at midnight

at dinner time

at the age of seventeen

at the end

at lunch time

at twenty five

at the last minute

at breakfast time

at the age of twenty five

at that time

at my age

장소의 at(손으로 가리킬 수 있는 좁은 개념)

at home

at the desk

at the station

at school

at the table

at the airport

at work

at the door

at the mall

at church

at the window

at the store

at the corner

at the beach

at the bottom 

at the top

at the party

I study at seven

I study at twelve

I study at dawn

I study at noo

I study at midnight

I study at Christmas

I study at Thahksgiving

I study at Halloween

I started studying at the age of twenty

I started studying at the age of ten

I study at home

I study at school

I study at the desk