还有一些事故主要是由起飞时引擎故障导致的。

There were also several accidents mainly caused by engine failures on take-off.

《柯林斯英汉双解大词典》

根据联合国的一份新报告，在过去20年里，极端天气事件的数量急剧增加，这主要是由全球气温上升引起的。

There has been a dramatic rise in the number of extreme weather events over the past 20 years, caused largely by rising global temperatures, according to a new report from the United Nations.

youdao

迁出市中心的现象非常普遍，而市中心的租户主要是由贫穷的劳动者组成。

Movement out of city centers was widespread, and downtown tenants were predominantly made up of the working poor.

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How can you write an original poem when your literary consciousness is essentially made up of the memory of all the things that you've read before?

你怎么能说自己写的是原创的诗,当你的文思,主要是由你以前阅读积累下的记忆,组合成的呢？

耶鲁公开课 - 弥尔顿课程节选

She was awarded tenure in 1938, denied a professorship for 18 years, and when she presented her Ph.D thesis she was the one that determined that the sun is made dominantly of hydrogen, not ion, the way most of the old goats thought.

她是在1938年被授予长期聘用资格，拒绝接受教授职位18年，她在她的博士论文写到,她就知道,太阳主要是由氢组成的，不是那些老教授认为的那样它是由离子构成的。

麻省理工公开课 - 固态化学导论课程节选

You need to do that to be able to control the shield that's as big as that and as heavy as that, because it is made fundamentally of a heavy wood, typically covered by leather, sometimes with some bronze, a bronze sheet across the front of it as well.

如果你想自如操控这块盾牌就必须得这样,这种盾牌很大并且很笨重,因为它主要是由沉重的木材制成,表面一般覆有皮革,或包上铜皮,就是表面上有一层铜皮

耶鲁公开课 - 古希腊历史简介课程节选