题型:选择题 —We should _______ humans from ________ down too many trees. —I agree with you. Trees are very important to us. A.keep; cutB.prevent; cutC.stop; cutD.prevent; cutting 查看答案
题型:单项选择题 大多数的膀胱上皮性肿瘤均为恶性,细胞类型依其发病率依次为()A.鳞癌、腺癌、移行细胞癌B.鳞癌、移行细胞癌、腺癌C.移行细胞癌、鳞癌、腺癌D.腺癌、鳞癌、移行细胞癌E.移行细胞癌、腺癌、鳞癌 查看答案