heart是不是可數名詞

　　It breaks my heart to see you like this.

　　看到你這個樣子我很難過。

　　It was clearly an offer that came from the heart.

　　那很明顯是由衷的提議。

　　His heart won't stand the strain much longer.

　　他的心臟對這種壓力承受不了多久。