As students, we should devote ourselves _____ our study.
His writing is so confusing that it's difficult to make out ________it is he is trying to express.
[2013·安徽卷] From space, the earth looks blue. This is ________ about seventyone percent of its surface is covered by water.
[2013·浙江卷] The only way to succeed at the highest level is to have total belief ________ you are better than anyone else on the sports field.
(2013·安徽,21)From space, the earth looks blue. This is ________ about seventyone percent of its surface is covered by water.
________ makes the book so extraordinary is the creative imagination of the writer.