_ is even important is ______ as the earthcooled down, water began to appear on its surface.

Taobao is Asia’s largest retail (零售的)network platform, ___ people can buy and sell manykinds of things[ ]

English _____one of _____subjects in the middle school.

255 The college entrance examination isdrawing near and all the students are ploughing through their studies Whatdoes the underlined part means _____

I often have conversations with John over ______ telephone, while keep in touch with Tom by ______ letter.