Has Bob been to this town before?

Has Bob been to this town before? Bob____all day.Could you speak to him now?A.phones D.has been phoning 我选A,为错了This kind of cloth ___very well.C.has been washed D.washes我选C,为什么错了I've heard that Bob _____ back from his journey to Africa.A has come D.had come我 This channel has been disabled due to a copyright This account has been blocked. this file has been damage This IP has been banned not only ..but also 不但.而且.代替.not only ..but also 不但.而且. 可换成什么...?eg.Not only Tom but also Bob has been to that island. ＿Tom and Bob＿been to that island. 1.Hello!May I speak to Bob?-Sorry,but he _____ for a month.A.had been away B.was left C.left D.has been away2.I ______ him since I began to live in the city,A.know B.have known C.knew D,will konw3.She _____ already ______ in this school for two years Mr Smith ___ at this school since he ___ to Zhuhai.A:has been taught; came B:has taught; has comeC:has been teaching; has come D:has been teaching; came为什么选D?has been teaching是什么时态? Sorry!an unexpected error has occurred.This error has been forwarded to MySpace's technical group. This is the third time the famous writer___the United AmericaA has been to B has been inC has come toD has gone to 这个题目选什么呀 where is bob?He _______America for a weekA has gone off to B has left for C has been off to D has set off to请说明原因, any transaction pursuant to this agreement that has not been completed prior to For several years this group (has been trying) to get the city government to help bicycle riders.为什么括号中用has been trying,而不是has tried? I know this has been hard.has been 是什么语法? has been to 和has gone to It has been 5 years since this party----.如题 It has been 5 years since this party----.用came to power 为什么不能用 in power Bob has to stay at home对stay at home提问() does Bob have to()