【单选题】北方民居庭院宽阔,南方民居天井狭小,其原因是 ______ 。
【单选题】It's said that the agreement ______ between the two companies last month will become effective from May 1.
【单选题】北方民居庭院宽阔,南方民居天井狭小,其原因是 ________ 。
【单选题】It's said that the emperor Shen Nong tea when he was boiling water. [ ]
【单选题】It's said that the sports meeting will be because of the heavy rain. [ ]
B.
put off C put away D. putin
【单选题】以下哪一条是观察的缺点( )
B.
过分强调儿童处于日常的自然状态,对刺激变量不加以控制,观察者常处于被动地位。
C.
观察记录要详细、客观、准确,不要带有任何主观偏见。
【简答题】小林为了探究燃烧需要哪些条件,他和同学们进行了以下探究活动: [提出问题]物质在什么条件下才能燃烧? [猜想与假设]要有可燃物质;氧气或空气;温度要达到着火点…… [设计与实验]在500mL的烧杯中注入400mL 开水,并投入一小块白磷(甲),在烧杯上盖上一片薄铜片,铜片一端放一小堆干燥的红磷,另一端放一小块用滤纸吸去表面水分的白磷(乙)。已知白磷的着火点为40℃,红磷的着火点为240℃。 (1)...
【判断题】It's said that the Carnival of Venice was started from a victory of the Republic of Venice in the year 1162.
【单选题】北方民居庭院宽阔,南方民居天井狭小,其原因是________。
【单选题】北方民居庭院宽阔,南方民居天井狭小,其原因是________。