Dãy chất chỉ gồm các oxit axit là: A. CO, CO2, CaO, Al2O3, N2O5 B. SO3, SO2, MnO, Fe2O3, N2O5 C. FeO, Mn2O7, SiO2, CaO, Fe2O3 D. N2O5, CO2, P2O5, SO2, SiO2

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Giúp mình nhanh với mình cho hay nhất và 5* ạ In the old days, people (believe) __ that the Earth (be) _________ flat. 186. The street (become) _________ very crowded after 5 pm every day. 187. The rivers (flow) _________ fast today – much faster than usual. 188. Everything is going fine. We (not have) _________ any problems so far. 189. My cousin (just/tell) _________ me about you. 190. I (help) _________ this woman last week. 191. _________ you (see) _________ Nam and Mai recently ? 192. We (eat) _________ this food several times. 193. My father (plant) _________ this tree 6 years ago. 194. He (not make) _________ any mistake yet. 195. What _________ he (do) _________ yesterday ? 196. They (go) _________ home after they (finish) _________ their work. 197. Who (speak) _________ at the meeting last years ? 198. Where _________ you (go) _________ for your holidays last year ? 199. She (not be) _________ here now. She (wash) _________ dishes. 200. Since I (be) _________ sick, I (not go) _________ on a picnic with you. 201. Rice (grow) _________ in tropical countries. 202. I (work) _________ for a computer company since I (graduate) ________ from university. 203. The house was very quiet when I (get) _________ home. Everybody (go) ________ to bed. 204. Mrs. Green always (go) _________ to work by car, but this week she (travel) _________ by bus. 205. I (write) _________ photographs every week. 206. Sorry, I’m late. How long _________ you (wait) _________ ? 207. People (speak) _________ English and French in Canada. 208. Don’t make noise. My mother (talk) _________ to his friends. 209. One day people (travel) _________ to Mars. 210. She’s going out. She (post) _________ these letters. 211. They (go) _________ to the zoo last Sunday. 212. Mai (learn) _________ English for 5 years. 213. His father (work) _________ in this factory since 1990. 214. Jane used to live in Hồ Chí Minh City, but now he (live) _________ in Hà Nội.