Another discovery about fish sounds is that not all fish are 13 "talkative."
答案：(B) equally
【字彙】equally 修飾 talkative，表示「並非所有魚都『同樣』健談」，呼應後文「有些魚話多、有些話少」的對比。merely（僅僅）、officially（正式地）、favorably（有利地）皆不符文意。
四個選項都是 -ly 結尾的副詞，形態上刷不掉，你只能一個一個放進去讀，挑一個順的。
四個選項都是副詞、都能修飾後面的形容詞 talkative，形態這條路斷掉，可見這一格考的是語意。關鍵在句首的 not all——「並非所有的魚都……」這個說法本身就在做比較：有的多、有的少。既然在比多少，空格要的就是一個講「程度相同」的字，也就是 equally（同等地、一樣地）。not all fish are equally talkative 的意思是「不是每一種魚都一樣多話」，緊接著的 Some species talk a lot, while others don't 正是在把這句話攤開來講。
merely（僅僅、只不過）是把程度往下壓（not merely 才是「不只是」），與比較多寡無關；officially（正式地、官方地）與 favorably（贊同地、順利地）在語意上都接不上 talkative。三個都是 -ly 副詞，形態吻合，容易被順手選走。
equally（同等地、一樣地）、not all（並非所有的，屬部分否定）、talkative（多話的、健談的）、merely（僅僅、只不過）、keep silent（保持安靜）、a wide repertoire（豐富的曲目、多樣的本事）。
The undersea world isn't as quiet as we thought, according to a New Zealand researcher. Fish can "talk" to each other and make a range of 11 by vibrating their swim bladder, an internal gas-filled organ used as a resonating chamber to produce or receive sound.
Fish are believed to speak to each other for a number of reasons, such as to attract mates, scare off predators, or give directions to other fish. Damselfish, for example, have been found to make sounds to scare off 12 fish and even divers. Another discovery about fish sounds is that not all fish are 13 "talkative." Some species talk a lot, while others don't. The gurnard species has a wide vocal repertoire and keeps up a constant chatter. Codfish, 14 , usually keep silent, except when they are laying eggs.
Any goldfish lover who hopes to strike up a conversation with their pet goldfish is 15 . Goldfish have excellent hearing, but they don't make any sound whatsoever. Their excellent hearing isn't associated with vocalization.