query: why "happen" is not given an "s" in this sentence? "I have seen it happen to friends."
positive_passages.docid: 13897
positive_passages.text: "He saw it stop and his son get out"
negative_passages.docid: 66131
negative_passages.text: Can a sentence start with "due to"?
negative_passages.docid: 99421
negative_passages.text: About the structure of ''There are/is''
negative_passages.docid: 23177
negative_passages.text: Tense change: previous actions on something that's currently true
negative_passages.docid: 74909
negative_passages.text: "Have you ever had surgery?" Why does surgery in this sentence have no article?
negative_passages.docid: 67781
negative_passages.text: "I have been there first time": Does this sentence sound awkward?
negative_passages.docid: 124981
negative_passages.text: About pronouncing the 's' in plural nouns
negative_passages.docid: 53075
negative_passages.text: Why do we say "try and" [verb] instead of "try to" [verb]? (E.g., "Try and call me tomorrow.")
negative_passages.docid: 121488
negative_passages.text: Why do we use "have" with does and not "has"?
negative_passages.docid: 101649
negative_passages.text: Can you use two "and"s in a sentence?
negative_passages.docid: 156723
negative_passages.text: Should I use "got" or "gotten" in the following sentence?
negative_passages.docid: 8622
negative_passages.text: Can a word be contracted twice (e.g. "I'ven't")?
negative_passages.docid: 24269
negative_passages.text: Difference between using a "-" and a "," in a sentence
negative_passages.docid: 117150
negative_passages.text: How could it had happened vs How could it have happened
negative_passages.docid: 8496
negative_passages.text: “I saw a dog” vs. “I have seen a dog”
negative_passages.docid: 135019
negative_passages.text: Why is "police" referred to using the singular pronoun "it" in this sentence?
negative_passages.docid: 155628
negative_passages.text: What is blocking a deictic use of 'it' in this example?