Answer:
Cliff jumping.
Volcano trekking.
Cave diving.
Kayaking for the first time ...
Mountaineering. (one day it'll happen)
The Rickshaw Run.
Syntax are important in a piece of writing because it is essential for written communication.
Without syntax, the sentences are harder to understand.
Example: Incorrect: While watching a movie, people who text on their phone are very annoying
Correct: People who text on their phone while watching a movie are very annoying.
It just makes the sentence easier to understand.
Hope that helps!