从1992年开始，重组的蛋白质开始大量的使用，如果真有的话，也只是包含一点人类的血液制品——因此，污染的危险是可以忽视的。

Since 1992 recombinant proteins are generally used, which contain little, if any, human blood products - and thus have a negligible risk of contamination.

youdao

If Korean students are having trouble with articles, I really recommend they don't get discouraged.

如果韩国学生学习冠词有问题的话，我真地建议他们不要气馁。

韩国人经常犯的失误 - SpeakingMax英语口语达人

If there are, let me know, I would love to meet that super model.

如果真有的话，告诉我，我还真想见见这样一位超级模特。

退休很神奇 - SpeakingMax英语口语达人