Detailed Instructions: In this task, you will be shown a correct English sentence. You need to generate an incorrect form of the input sentence.
See one example below:
Problem: Students shouldn't work multiple full-time jobs.
Solution: Student's shouldn't work many full-time jobs.
Explanation: The possessive form is not correct in this instance and many should be multiple.

Problem: Tour guides are generally trained and certified by some supervising entities , therefore they are expected to be ready to provide the best possible guidance to their customers . 
Solution:
Tour guides are generally trained and certified by some supervising entities , therefore they are expected to be ready to provide the best possible guide to their customers . 