How do native speakers use prepositions without getting confused? There are many prepositions in English sometimes I'am confused of those prepositions.How do you treat those preposition or is it necessary to use them strictly?

My Daily Today I finished my English exam.Once i stepped out of the classroom,i felt'oh!too bad,i might have failed my exam again.'The room was cold because it's a lecture theatre and the tempreture is below freezing,besides,there is no air condition in this room.I think this is the coldest day ever this winter.My English is so poor that i could hardly finish the whole paper.I'll appreciate it that if anyone tells me how to improve my reading speed and reccomend some good and easy books for me.Think u.>"<

Bad day Today is axam day,we had chinese this morning and math is afternoon.I hate math for i make careless mistakes easily and i think am not intelegent enough to learn math.students in china were foced to be a behaved child since the first day at school.though i am used to it,i still feel stressed from time to time.i real wonder what life of high school students in the us or europe be like.