填入下面一段文字横线处的语句，最恰当的一项是某一地区特定时间内游客数量超过其接待能力，是造成该地区旅游业出现种种问题的重要原因。若不提高其接待能力，再美丽的湖光山色也会暗淡无光， ，再动人的微笑服务也会丧失魅力。

(2013·江西六所重点高中一模)We ________ take clean drinking water for granted. One day we may run out of it.

The number of the students in our school isabout nine _____. —I see. ______of them are boys.

d a computer at home, and her parents desiredthat she _____all her work at home

I don’t know _______ he will come tomorrow. ________ he comes, I’ll tell you.