41.He came back late, _______ which time all the guests had already left. A) after B) by C) at D) during 42.I'm very sorry to have _______ you with so many questions on such an occasion. A) interfered B) offended C) impressed D) bothered 43.If the whole operation _______ beforehand, a great deal of time and money would have been lost. A) was not planned B) has not been planned C) had not been planned D) were not planned 44.The price of beer _______ from 50 cents to $4 per liter during the summer season. A) altered B) ranged C) separated D) differed 45.His remarks left me _______ about his real purpose. A) wondered B) wonder C) to wonder D) wondering 46.I have heard both teachers and students _______ well of him. A) to speak B) spoken C) to have spoken D) speak 47.Our son doesn't know what to _______ at the university; he can't make up his mind about his future. A) take in B) take up C) take over D) take after 48.The house was very quiet, _______ as it was on the side of a mountain. A) isolated B) isolating C) being isolated D) having been isolated 49.Although they plant trees in this area every year, the tops of some hills are still _______. A) blank B) hollow C) vacant D) bare 50.Being a pop star can be quite a hard life, with a lot of travelling _______heavy schedules. A) with regard to B) as to C) in relation to D) owint to 51.Tony is very disappointed _______ the results of the exam. A) with B) for C) toward D) on 52.William Penn, the founder of Pennsylvania, _______ defended the right of every citizen to freedom of choice in religion. A) peculiarly B) indifferently C) vigorously D) inevitably 53.I hope all the precautions against air pollution, _______ suggested by the local government, will be seriously considered here. A) while B) since C) after D) as 54.When people become unemployed, it is _____ which is often worse than lack of wages. A) laziness B) poverty C) idleness D) inability 55.I've never been to Beijing, but it's the place _______. A) where I'd like to visit B) in which I'd like to visit C) I most want to visit D) that I want to visit it most 56._______ his sister