Because COPD is an ailment that blocks airflow in the lungs, it is critical that COPD patients often focus on breathing, exercise regularly and learn relaxation techniques, especially when they are short of breath.

VOA: standard.2010.06.21

So it's something you should learn easily and use often.

因此这是个你好掌握的句型同时要活学活用。

When 课堂 - SpeakingMax英语口语达人

So it's something you should learn easily and use often.

因此这是个你好掌握的句型同时要活学活用。

When 课堂 - SpeakingMax英语口语达人