Sometimes up, sometimes down.

有时候上去，有时候下去。

youdao

Pipe smokers sometimes wear down the tips of their teeth where they grip their pipes.

抽烟斗的人用牙齿咬住烟斗，有时会把牙齿尖磨平。

《柯林斯英汉双解大词典》

Watching your wealth build can be like watching the grass grow; sometimes the mower comes in and cuts everything down.

看着你自己的财富积累就像看着草丛生长；有时割草机会进来，将一切砍倒。

youdao

Sometimes her pictures made you feel you were looking down from a great height, or up from far below.

VOA: special.2009.05.10

So, the bowlers do their bowling and sometimes they knock down all the pins, which is called a what? A strike.

投球手投球时,有时他们撞到了所有障碍物，这叫什么呢，全打。

耶鲁公开课 - 心理学导论课程节选

Sometimes we can't help but slow down because everybody is slowed down in front of us, we have no choice.

有时我们不得不慢下来因为前方,每个人都已减速，我们别无选择。

耶鲁公开课 - 政治哲学导论课程节选

Conversations about schoolwork take on new zest when, rather than a specific work of literature or history, you are wrestling with the English language itself, sometimes pinned down by an immigrant youth, and sometimes throwing and clobbering the youth instead.

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The money was good enough, in fact, that he sometimes turned down raises.

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And while we sometimes fall down on the job, we bring to the political arena a certain battle-hardened skepticism.

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