由语境Some dogs can tell if someone is about to have a heart attack...they can warn them before it happens.(有些狗能分辨出某人是否即将心脏病发作……他们就能在事情发生前警告他们。)可知,此处表示结果,作为句首首字母应大写,应填So,故填:So。(10)考查动词过去分词。句意
What is the best way to change someone else's mind? Take a look at this quick marketing video and see.