Answer:
How to avoid getting scammed in foreign (European) countries
Where to find tour guides to help you through your country of choice
Those are just a few that you said you needed. If you need more I may be able to come up with a couple extra. It's kinda hard though!
One of your students forgot their book on the table.
D because it includes more information than the others and is more professional
Subject and Verb do not agree. Sequoia and Charles plan to exercise together.
The subject of this sentence is a compound subject (Sequoia and Charles). A compound subject is a plural subject because it has more than one. The verb "plans" agrees with a singular subject because it ends with /s/. In order to make the subject and verb agree, the /s/ at the end of "plans" needs to be eliminated. The revised sentence should be "Sequoia and Charles plan to exercise together."