maintain是系动词吗
maintain不是系动词。Mankindhavebeentryingeverymeanstomaintainthebalanceofnature.人类采用一切手段保持生态平衡。Wemustmaintainafirmattitude.我们必须采取坚定的态度。Thegovernmenthastakenameasuretomaintai...
maintain不是系动词。Mankindhavebeentryingeverymeanstomaintainthebalanceofnature.人类采用一切手段保持生态平衡。Wemustmaintainafirmattitude.我们必须采取坚定的态度。Thegovernmenthastakenameasuretomaintai...