Not all subject islands are equally strong. Some violations become acceptable if they are "saved" by a second gap in the sentence, known as a .
Some researchers suggest the problem isn't grammar, but . Islands
A occurs when the grammatical subject of a sentence acts as one of these barriers. In English, you can usually extract a word from the object of a sentence, but doing the same to the subject results in an ill-formed "island violation". Not all subject islands are equally strong