单项选择题
Water is an essential global resource and it is up to each of us to ______ it.
单项选择题 3-G takes ______ market share. In the last quarter, 20% of the sales were 3-G phones.
单项选择题 The irresponsible teacher knew the student was cheating but decided to look ______.
单项选择题 The actress wanted a hat, to ______ her dress.
