No. The 2008 Olympics - is plural so the verb phrase - was held - should be plural.
The 2008 Olympics were held in Beijing.
They are both correct.
It is correct.
The corrected sentence should have verb-subject agreement as well as pronoun-antecedent agreement with no misplaced modifiers to be grammatically right.
He agrees with you. Or he is in agreement with you.
A simple sentence.
I saw a leaf in the ground
A simple sentence need both subject and predicate to agree to be correct.
Yes. Best to keep the verb agreement, if possible.
The sentence "It lacks agreement Possible correct alternatives are He is the one of the men who does the work or He is one of the men who do the work" are not of correct grammar.
The English sentence "Neither Kyle not his brother are interested in bask" does indeed show the correct subject-verb agreement. For further advice on grammatical matters, try the "Grammarly" website.
Jim and Mark have been friends since first grade.
In a grammatically correct sentence there must be a subject,verb and object agreement.