【单选题】硅胶柱色谐法分离下列黄酮类化合物,最先流出色谱柱的是
【单选题】The speaker worried about
【简答题】There is no denying that + S + V ...(不可否认的...)
【单选题】Many experts seem to agree that certain limit should be set on consumption of cars to ease air pollution.
【单选题】以下不可否认业务中为了保护发信人的是()
【简答题】(不可否认)that air pollution is harmful to human health.
【单选题】不可否认业务中,用来保护收信人的是( )