问题详情：
There's no such thing as living alone. Never mind if you're 41 only person in your house and have no dog, no cat, not even fish. You still have got several billion 42 (roommate)—and so do we all. Some of them are harmless, some are 43 (actual) helpful and some could even kill you. They are, of course, bacteria, fungi (菌类) and viruses, and like it or not, they're on you, around you, and deeply within you. The fact that bacteria life is everywhere is not 44 (surprise). It's something you 45 (learn) from your childhood when your mother told you not to drink water from someone else's glass. There are lots of bacteria 46 are living in your tea kettle. There are bacteria 47 (sleep) with you on your bed. Scientists are beginning to realize the 48 (rich) of the microbiome (微生物群系)—which is as complex as the ones 49 (find) in oceans, rainforests, deserts and woodlands. Your house has a microbiome and 50 do you.
【回答】
41．the the only唯一的。
42．roommates 该处用复数名词。
43．actually 修饰形容词用副词。
44．surprising 修饰物用ing形式。 surprising令人吃惊的。
45．learned from your childhood与一般过去时连用。
46．which/that 先行词为物，定语从句缺主语，用which/that引导。
47．sleeping 现在分词作定语。
48．richness the后跟名词。
49．found 过去分词作定语。
50．so so＋助动词＋主语，意为“某人也如此”。
知识点：语法填空
题型：未分类
