【单选题】Great changes have taken place since then in the primary school _______I am studying.
【单选题】选择模式生物进行研究是生物学研究的一种捷径,下列哪个适合于做原核生物的模式生物?( )
【单选题】原核生物的哪一种DNA聚合酶还具有5’到3’外切酶活性
【单选题】原核生物核糖体的 30S 小亚基中含有哪一种 rRNA
【单选题】—How do you like China? —Great changes _______ since I _______ here 8 years ago.
A.
have taken place; came
【单选题】Great changes ______ in China since1978.
【单选题】Great changes ________ in the city since 1979.
【单选题】Great changes______ in the city since1970.