(留有)Word Power: -tain

-tain: hold, keep
1.
sustain 維持: allow sth. to continue/keep alive
e.g. The soil of this land is rich enough to sustain the large population.

maintain 保持: continue to have/keep in good condition
e.g. Although they live apart, they maintain close links.

2.
attain 達到: reach sth.
e.g. He attained the highest grades in class.

obtain 取得: get
e.g. The Chinese version of the novel is almost possible to obtain now.

3.
contain 容納: hold
e.g. How much water does the bottle contain?

retain 保有: continue to have sth.
e.g. The Qing Empire lost the war to retain the control of Hong Kong.

4.
detain 拘留: force sb. officially to stay in a place
e.g. A suspect has been detained by the police.

References:
1. 臺灣鳳山高中吳姿瑩老師
2. http://dictionary.cambridge.org/