2. As the housing affordability gap widens, middle-income families are especially hard-hit, and these families can no longer qualify to buy homes, and rising rental rates force them to use far more than the standard 25 percent of their incomes for housing, leaving them with no equity or tax write-offs to offset the expenditures. (A) and these families can no longer qualify to buy homes, and (B) since these families can no longer afford to buy homes, furthermore (C) for these families can no longer afford to buy homes, yet (D) and these families can no longer afford to buy homes, yet (E) and these families can no longer afford to buy homes, for 我选了b，b为什么错呢？
3. Confused by the many strata and substrata of ancient civilizations overlying one another, Schliemann’s excavations of the fabled city of Ilium, the ancient Troy, were temporarily called to a halt. (A) Schliemann’s excavations of the fabled city of Ilium, the ancient Troy, were temporarily called to a halt (B) Schliemann’s excavations of the fabled city of Ilium, the ancient Troy, temporarily halted (C) Schliemann temporarily halted his excavations of the fabled city of Ilium, the ancient Troy (D) excavations of the fabled city of Ilium, the ancient Troy, were temporarily halted by Schliemann (E) excavations of the fabled city of Ilium, and of the ancient Troy, were temporarily halted by Schliemann 答案是c，我选了d。c中间confused的逻辑主语是什么？
23. Of the twin supernovas, the most recently discovered is the largest, but it is the small one that has irrevocably altered astronomists’ ideas about the origins of the universe. (A) the most recently discovered is the largest, but it is the small one (B) the one most recently discovered is the largest, but it is the small one (C) the most recently discovered is larger, but it is the smaller (D) the more recently discovered one is the large one but the small one (E) the more recently discovered is the larger, but it is the smaller one 这题的答案是e，我选了b。也不是很明白这题的考点。
