mental disorder / psychiatric condition：
心理障礙，心理疾病

ADHD -- Attention Deficit Hyperactivity Disorder
注意缺陷多動障礙
It's characterized by not being able to pay attention, fidgeting a lot, always moving, not being able to focus.
它的特征是注意力難以集中，常常坐立不安動來動去的。
fidget 坐立不安，煩躁
Sit still and stop fidgeting!
坐好，不要動來晃去的！

ASD -- Autism spectrum disorder
自閉癥，孤獨癥
autism 自我中心主義 （aut-自己，ism-主義）
It refers to a broad range of conditions characterized by challenges with social skills, repetitive behaviors, speech and nonverbal communication.
它指的是一種影響廣泛的疾病，特征是社交障礙，重復性行為和語言，不愛開口說話。
We know that there is not one autism but many subtypes. Most influenced by a combination of genetic and environmental factors.
自閉癥有很多不同的類型。大部分都是由于遺傳學因素和環境學因素的共同影響。

Bipolar disorder
雙相情感障礙，躁郁癥
Another common mental illness is called Bipolar disorder, also known as manic-depressive disorder. A mental disorder that causes periods of depression and periods of mania or hypomania.
另外一種疾病叫做雙相情感障礙，又叫做躁郁癥。會導致持續性的或抑郁或狂躁的心情。

MPD -- Multiple Personality Disorder
人格分裂，多重人格障礙
multiple 多種多樣的，數量多的