Please help why does an author use irony?

hm, switch the relative; nominative and indefinite; objective ? not too bright in the knowledge of the english.

the development of trade during the middle age increased to the change given in the agriculture, which gave money, industry and markets a bigger importance in economy. the agriculture production was more than the consumption, which meant the creation of wider markets out of the areas. besides, with the end of multiple wars, the population increased and new trade routes were created.

they should gives us more chances to make friend and do stupid things

the tree invited all its friends to its lumber party. the party was at saruman's tower in isengard because saruman had killed some trees