31. --- Why were you late for class this morning?
--- Because I o .
32. The fire won't b because the flue is blocked up.
33. Lucy's favorite dessert is ice c , although she knows it's bad for her health.
34. As she is ill, we have to (取消) our trip to the West Lake.
35. When spring comes, the snow and ice (消失).
36. The rain (stop) when she woke up and the sun was shining brightly.
37. It is (luck) for him to lose his wallet and cell phone on the playground.
38. After the clock went off, she woke up and then got (dress).
39. New scientific (discover) are made every day.
40. Her explanation certainly sounded (believe).