【英语时差8,16】鱼的性格-上

（单词翻译）

Hot periods in July and August are called the dog days of summer because they do more than make a person sweat. People’s personalities¹ change. They become tired and irritable². Tempers shorten. Many prefer lounging like a dog rather than working. It appears that humans aren’t the only animals that can have dog days in hot temperatures. Research has found that fish can have them too. Scientists have been investigating fish personality for quite some time. Some fish are shy and reserved, not venturing far from their protective habitat, and ducking for cover rapidly when threatened by new stimuli³. Other fish are bolder, swimming out into the open more and acting⁴ aggressively to newly introduced objects and fish.