困难 1.(事情复杂,阻碍多) difficulty; difficult; hard; bump; rub 说话困难 be difficult to talk; 困难的工作 difficult work; hard work; 困难留给自己, 方便让给别人 difficulties for oneself but conveniences for others; 你听懂英语有困难吗? do you have [find] any difficulty in understanding spoken english?2.(生活穷困) financial difficulties; straitened circumstances 生活困难 live in straitened circumstances; 困难户 families with material difficulties
哺乳动物 mammal; mammality; mammalian 海洋哺乳动物 marine mammal; 鲸是一种哺乳动物。 a whale is a kind of mammal.; 哺乳动物毒害 mammalian toxicity; 哺乳动物纲 mammalia; 哺乳动物时代 age of mammals; 哺乳动物学 mammalogy; therology