Multipurpose Internet Mail Extension (MIME) is a (76) document messaging standard in the Internet environment. With MIME, users can send (77) E-mail messages that include audio, video, graphices, and text to any other user of a TCP/IP network. Richtext information can also be (78) into messages. It defines the fonts, formats, and (79) features of a document so the document can be easily (80) on many different types of systems.

A．complete

B．compound

C．simple

D．efficient

教师在教学中教会学生学习“going”的“ing”，再教学生学习“playing”“coming”就能达到事半功倍的效果，可以解释这种学习现象的是（）。

A.共同要素说

B.形式训练说

C.概括化理论

D.实质训练说