1、lack,缺乏,詞組:be lack of 缺乏。We are lack of  water very much.我們十分缺乏水資源。
2、back,背部,The back pain left the patient suffering.
背部疼痛讓這個病人受盡了折磨。例:
He opened the back door.
他打開了後門。
Ann could remember sitting in the back seat of their car.
安能記得曾坐在他們車子的後座上。