【单选题】—Where have you been ? I have been waiting here for half an hour. —I have been to that_____to buy a present for you.
【单选题】What are doing here? I ________ for you for ages!
【单选题】The Smiths _______ China for ten years , so they have been used to the life here.
【多选题】强调文学离不开世界、世界是文学之源的文论有( )。
【单选题】在实验时为促使凝集现象的出现,下列措施无效的是
【简答题】四冲程汽油机与柴油机工作原理的比较有什么相同点和不同点?
【单选题】—_______ have you been here? —I have been here for moths. [ ]
【单选题】在实验时为促使凝集现象的出现,下列措施无效的是
【单选题】四冲程柴油机和汽油机工作原理不同,以下说法错误的是()。
【简答题】四冲程汽油机和柴油机的工作原理、相同点和不同点分别是什么?