Add "a","an" or "the" to these pairs of sentences where necessary

Add "a","an" or "the" to these pairs of sentences where necessary
1.we are staying in hotel.hotel is on church Street.
2.There is window in our classroom.I sit near window.
3.shenzhen has new shopping mall.shopping mall is in futian district
4.I have red shirt and green shirt.Red shirt is too small and green shirt is too big
5.We have English grammar exercise for homework.I can't understand exercise