"doesn't know" vs "don't know"
76427
Is "It is you who are mistaken!" correct?
42843
What are the differences between "seems not" and "doesn't seem"?
54106
"I assume you know" vs. "I am assuming you know"
15721
"Is it proved that ...?" vs. "Has it been proven that ...?"
28837
What is the difference between "Have you seen this?" and "Did you see this?"
23132
"Why didn't (or did not) somebody do something?" or "Why did somebody not do something?"
33321
Is "if you're not familiar with X, it is..." or "if you're not aware, X is..." correct English?
24661
"had they known" or "if they had known"
119719
"Do" vs. "does" with multiple singular subjects
51157
'Wouldn't wake up' vs. 'didn't wake up'
37279
"can't" versus "couldn't", what is the difference?
655
"How it works?" vs. "How does it work?"
132461
NOT IN vs NOT EXISTS
42496
What is the purpose of using "don't" instead of "doesn't" in this phrase: "But she don't know you like I know you Slim"
141279
Is there a difference between  and ?
146182
"How come" vs "Why?"
46700
What the matter is vs. what is the matter used in the affirmative