19.Narwhals usually bottom out around 10 beats per minute, but the researchers saw that as they swam away, their heart rate went much lower, to under 4 beats per minute.
20.The economy may even shrink in a period of contraction or contract in a slowdown – get smaller – before it reaches a trough or bottoms out and starts to grow again.
济甚至可能在收缩期收缩或在放缓期收缩——变得更小——然后才达到或触底反弹并开始再次增长。机翻
「Business Vocabulary in Use Advanced 3rd Ed」评价该例句:好评差评指正