Colloquail English writing are informal or contain informal or everyday language like what's up and mostly contain contracted forms of words and street terms. Examples of such writings are friendly letters or letters written to agemates like friends. Formal writings on the other hand are written differently. All words are written in full form and the proper form of English is used. Example of such writtings are formal letters or letters written to people of high offices or authority.
A.
They decided to meet where the band was performing.
Answer:
After returning from the past, he was left without understanding why he was not selected for the Slytherin but for the Gryffindor.
Explanation:
This question is about "Harry Potter and the cursed child", when he uses the necklace that allows time travel, to go to the past. On this trip he is faced with innumerable information that leaves him confused, mainly in relation to him and his father. When he finishes watching and returns from the past he is very thoughtful and does not understand why he was selected for the Gryffindor, since the past shows that he must have been in the Slytherin.