Thank you, Hoa Thai. I have two more questions, if you are willing to lend a helping hand.
1. I wrote this in the original inquiring post:
Once you enter the premises, you will see desks with a piece of paper that has a capital letter written on it. You are to find the letter that corresponds to the first letter of your last name and check-in. After you have signed your name and the person at the desk have confirmed your payment of the registration fee, you will be given a name tag and will be told where to go next. You will see plenty of refleshments on various locations and people with 'Ask Me' badges all over the place to get help.
And for that you seemed to question the use of the present perfect for the underlined parts. Personally, I think it is possible for me to use the past perfect tenses there because I think I have heard this type of tense being used in this kind of context.
Employer: OK, John, go and deliever this package to the two places I marked on this piece of paper. Go up this street and turn right after two blocks. Right next to the movie theater, you will see the "ZZZ Hardware" store. Get in there and give this to the manager. After you have delivered the first package, you are to head up two more blocks and find ...
The task of delivering the package hasn't begun, but I think the use of the present perfect in one's instructions is fine. What do you think?
2. Also, would you say that the basic reason for placing 'that' here is because the word 'place' is a subject (although it is the subject of a modifying clause) and since it is a subject, 'that' isn't optional. Does it sound correct to you?
..., since the place that they will attend will be obvious ...