DAP是电器和仪表部件中常用的一种高分子化合物,其结构简式如下:则合成它的单体可能有①邻苯二甲酸 ②丙烯醇 ③丙烯 ④乙烯 ⑤邻苯二甲酸酯,正确的是
The children all turned ____ the famous actress as she entered the classroom.
Edward, you play so well. But I ______ you played the piano.
She brought with her three friends, none of ______ I had ever met before.
I tried phoning her office, but I couldn’t _______.
His sister left home in 1998, and _______since.