1. A. on
The correct preposition is "on", as it refers to a specific date, "on September 20."

2. B. who
The appropriate word here is "who", as it refers to people (special speakers) who will share their perspectives.

3. A. opportunity
"Opportunity" fits best as it conveys a chance to learn more, which is what the event provides.

4. A. the
The correct article is "the", as it refers to a specific spot at the event that needs to be secured.

Second Passage:

1. D. packed
The correct word is "packed" as it implies the roads are often filled or crowded with traffic.

2. B. entertainments
"Amenities" or "entertainments" would work, but "amenities" seems more fitting for public places and facilities like parks or restaurants.

3. C. use
"Use" works best because it talks about utilizing the transport systems.

4. B. but
"But" is correct because it introduces the contrast that even though life in the city can be chaotic, people still like it.

5. D. exciting
"Exciting" fits the context best, as it refers to the lively nature of city life that attracts people.

1. D. to 
2. B. who
3. A. opportunity
4. B. a

1. D. packed
2. A. amenities 
3. C. use 
4. B. but 
5. D. exciting