The internal speech is the main medium of thought.

内在的言语是思维的主要媒介。

youdao

Stupendously, mobile telephone has developed as the main medium of social transmitting.

手机以惊人的速度迅速成为人际传播的主要媒介。

youdao

Chinese at a higher level than other schools and with greater cultural content, but the main medium of instruction is English.

校内所教的华文，程度会比较高，文化成分也比较多，但主要的教学媒介还是英语。

youdao

However, he said print remained the main medium for the island's strategy throughout the season.

BBC: Guernsey to increase tourism adverts on internet

Normally television advertising, the main medium for reaching the electorate, would help.

ECONOMIST: The South Dakota Senate race

He came to fame by skewering small towns (in Main Street) and medium-size heartland cities (in Babbitt).

FORBES: California Leavin'